Add github.c and github.h (#9)

* Add github.c and github.h

* Implements get_github_release_notes()

* Remove unused variables

* Fix circular dependency on tplfunc_frame

* Remove predeclaration of tplfunc_frame
* tpl_register_func accepts pointer to void instead
* tpl_register_func sets maximum number of arguments
* Frame is generated within tpl_register_func

* Improve template function error handling and return/output management

* Remove redundant extern statement

* Include github.h and template_func_proto.h in core.h

* Expose get_github_release_notes_tplfunc_entrypoint function to template engine

* Add template_func_proto.c and template_func_proto.h

* Replace free() with guard variant

* Fix test_template::test_tpl_register_func

* Fix tests

* Fix tests

* cmd should be at least PATH_MAX in size.

* Magic number caused failure to install conda with a long installation path

* Implement get_github_release_notes_auto function that bases release note data off test contexts

* Disable overwriting releases by default

* Add automatic release note generation function call to release_notes.md.in

* Fix test_tpl_register_func()

* Add enough space for tar command plus a path

* Fix circular include

* Github functions do not require access to core.h anyway

* Add comments to union

* Update README to mention template function availability

* Add EnvCtl structure
* Add runtime checks to avoid running all the way to the end only to be met with a configuration error.
* Rename GITHUB to GH

* Development docs pre-rough-draft

1 files changed, 24 insertions, 15 deletions

diff --git a/README.md b/README.md
index c3e9db6..baa0864 100644
--- a/README.md
+++ b/README.md
@@ -143,21 +143,22 @@ stasis mydelivery.ini
 
 ## Environment variables
 
-| Name                                | Purpose                                               | 
-|-------------------------------------|-------------------------------------------------------|
-| TMPDIR                              | Change default path to store temporary data           |
-| STASIS_ROOT                         | Change default path to write STASIS's data            |
-| STASIS_SYSCONFDIR                   | Change default path to search for configuration files | 
-| STASIS_CPU_COUNT (alias: CPU_COUNT) | Number of available CPUS                              |
-| STASIS_JF_ARTIFACTORY_URL           | Artifactory service URL (ending in `/artifactory`)    | 
-| STASIS_JF_ACCESS_TOKEN              | Artifactory Access Token                              | 
-| STASIS_JF_USER                      | Artifactory username                                  | 
-| STASIS_JF_PASSWORD                  | Artifactory password                                  | 
-| STASIS_JF_SSH_KEY_PATH              | Path to SSH public key file                           |
-| STASIS_JF_SSH_PASSPHRASE            | Password associated with SSH public key file          | 
-| STASIS_JF_CLIENT_CERT_CERT_PATH     | Path to OpenSSL cert files                            | 
-| STASIS_JF_CLIENT_CERT_KEY_PATH      | OpenSSL key file (in cert path)                       | 
-| STASIS_JF_REPO                      | Artifactory "generic" repository to write to          | 
+| Name                                      | Purpose                                                                 | 
+|-------------------------------------------|-------------------------------------------------------------------------|
+| TMPDIR                                    | Change default path to store temporary data                             |
+| STASIS_ROOT                               | Change default path to write STASIS's data                              |
+| STASIS_SYSCONFDIR                         | Change default path to search for configuration files                   | 
+| STASIS_CPU_COUNT<br/>(alias: CPU_COUNT)   | Number of available CPUs                                                |
+| STASIS_GH_TOKEN<br/>(alias: GITHUB_TOKEN) | GitHub API token<br/>(Scope: "Contents" repository permissions (write)) |
+| STASIS_JF_ARTIFACTORY_URL                 | Artifactory service URL (ending in `/artifactory`)                      | 
+| STASIS_JF_ACCESS_TOKEN                    | Artifactory Access Token                                                | 
+| STASIS_JF_USER                            | Artifactory username                                                    | 
+| STASIS_JF_PASSWORD                        | Artifactory password                                                    | 
+| STASIS_JF_SSH_KEY_PATH                    | Path to SSH public key file                                             |
+| STASIS_JF_SSH_PASSPHRASE                  | Password associated with SSH public key file                            | 
+| STASIS_JF_CLIENT_CERT_CERT_PATH           | Path to OpenSSL cert files                                              | 
+| STASIS_JF_CLIENT_CERT_KEY_PATH            | OpenSSL key file (in cert path)                                         | 
+| STASIS_JF_REPO                            | Artifactory "generic" repository to write to                            | 
 
 # Variable expansion
 
@@ -205,6 +206,14 @@ version = {{ env:MY_DYNAMIC_DELIVERY_VERSION }}
 python = {{ env:MY_DYNAMIC_PYTHON_VERSION }}
 ```
 
+## Template Functions
+
+Template functions can be accessed using the `{{ func:NAME(ARG,...) }}` notation.
+
+| Name                          | Purpose                                      |
+|-------------------------------|----------------------------------------------|
+| get_github_release_notes_auto | Generate release notes for all test contexts |
+
 # Delivery files
 
 ## Sections