Extract report creation and sending from _run()

I moved the report creation and sending functions into their own
`report` module.
Move ReportCreator creation up to main()

This required replacing a __FILE__-based call with pkg_resource, which
fixes ctsit/redi#99.
Make ReportCreator constructor more explicit
Update unit tests
Cleanup import statements

Replaced get_proj_root() with pkg_resource equivalent. Removed unused
argparse import.
Merge pull request #103 from ufl-taeber/reporting-refactor

Reporting refactor