Filter: better colour selection for 'rainbow'
Merge pull request #965 from GLolol/mirccolors-dict

ircutils: also map zfill'd versions of integers in mircColors
Merge pull request #967 from GLolol/filter/better-rainbow

Filter: better colour selection for 'rainbow'
Remove 2to3/__pycache__ before making a source dist. Closes GH-946.
Merge branch 'testing' into lilybot