Update Release Notes - Add Date
Move version -- Remove dev tag
Fix non-iterable when flags is empty bug
Move `which` method from test to task

Add `in_path` method. Update test to use new methods
Reorganize task imports -- one line per item

May be a bit more verbose, but maintains line length less than 79 characters.

Add new methods `which` and `in_path`
Add check for testing python2 explicitly
Increment dev version
Add tests for tex build module
Refactor parameters in make module: require target
Add tests for the make module

Theses tests are _not_ testing the result of running the actual sub build
command; but, rather, the test purely the ability to invoke them at all.
Merge 'add_build_make_tex_tests' into develop