Retrofit the reporting system to be a subsystem.
Review Request #2226 - Created May 14, 2015 and submitted
Note that reporting/reporting.py is a near-copy of the old
goal/initialize_reporting.py. The two free-standing functions
are now methods.
Manually verified that the reporting system still works.
CI passes: https://travis-ci.org/pantsbuild/pants/builds/62622918 .
Status: Closed (submitted)
Submitted as d203da81f9dd5e82258adf0bc1dd9d027464886f. Thanks John!