[weather] Fix error when receiving an unknown place name

Added a bit of error checking.
[rss] Add a docstring to main command function

This somehow got overlooked when refactoring.

Also added a doc line for fg/bg colours.
[rss] Avoid error looking for HTTP status when fetching non-web feed

Feedparser will not return a status attribute if fetching from a feed on
disk or in memory, so added a check for its existence.
[config] respect homedir config value when enumerating modules

This should fix issue #336
[config]close #338 by adding missing quotes
[meetbot] Allow comments from outsiders to be shown

Extra commands allow sending comments, and showing them when the chairs
want. This is primarily for NFIRC board meetings, where
non-board-members aren't given voice, but we still want to hear from
them after each topic. Others may find it useful, too.
Merge pull request #335 from saltire/rss

[rss] Improved documentation, fix error when parsing non-web feed
Merge pull request #333 from saltire/weather

[weather] Fix error when receiving an unknown place name
Fix the stderr call since stderr expects one argument, a string
Merge pull request #342 from DePierre/fix_stderr

Fix the stderr call since stderr expects one argument, a string