* Move headers to relevant include directories within the target tree(s)
* Adjust doxygen configuration to search correct paths
* Adjust CMake configuration to use new include paths

Includes minor changes:
* Rename jfrt_upload_set_defaults to jfrt_upload_init
* Move jfrt_auth_init to artifactory.c
* Adds missing error handling to git_describe and git_rev_parse

* Returns HTTP status code
* Emits curl error message to stderr (or to a buffer if the third argument is not NULL)