add support for fetching easyconfigs from a PR via eb --from-pr
add unit test for --from-pr
make sure PR is in a 'clean' mergeable state
fix using post with authentication in agithub module
add --github-token, --github-user and --test-easyconfigs-pr command line options
add functions to create a gist and post a comment in an issue
implement support for reporting back with PR test result
fix typo
fix another typo
add support for fetching GitHub token from keyring
get rid of github_token cmdline option to avoid leaking tokens via logs, etc.
further flesh out reporting back on tested easyconfigs PR
include time, system and EasyBuild info in test report
include short system info in comment, reenable posting comment
add module list, dump of environment, EasyBuild configuration, libc version in test report
Merge branch 'develop' into test_pr

Conflicts:
	easybuild/main.py
get rid of unused --regtest-online option
catch any exceptions occuring per build, improve reporting of failed builds
improve error message on failed HTTP request to GitHub API
catch exception occuring during download