* Change return value of conda_setup_headless() from void to int
* Replace exit() with return;
* Return early if unpacking the micromamba binary fails
* Exit program when pointer to INIFILE is NULL.
* Validation function cannot otherwise proceed
* The way the logic is set up I've decided to duplicate the installation code for now until I find time to revise it
* The only meaningful difference between a "fresh start" and reusing the conda installation is a rmtree().
* Exposes STASIS_DOWNLOAD_TIMEOUT environment variable
* Sets the connection timeout for libcurl to 30, instead of 300.
* Export ini_section_create() function
* Add download() tests
* Add conda_*() tests
* Add boilerplate source file for test framework
* Fixes segfault reported by @GeorgeJCleary (#10)
* The key is now an array index. When key is -1, the env variable is not defined.
* Free resources only when continue on error is disabled (#11)
* Fix segfault due to premature shutdown/cleanup
* If conda_setup_headless cannot succeed, die
* Set STASIS_SYSCONFDIR for tests