Aka: add 'list' command (Closes ProgVal/Limnoria#572)
Aka: update listCommands override to only include built in cmds

The old behavior is superseded by 'aka list'. This makes it easier for people to find Aka plugin's core commands, as
'list Aka' won't be filled with random, irrelevant alias definitions.
Aka: update tests
Aka: catch with error if 'aka list' response is empty
Aka: update list command
Aka: update converters to use 'channel' instead of 'somethingWithoutSpaces'
Merge branch 'testing' into aka-2

Conflicts:
	plugins/Aka/plugin.py
Revert "Aka: update converters to use 'channel' instead of 'somethingWithoutSpaces'"

This reverts commit 231c250b75357988cdc48ab91656c3043f9fdcec.
Aka: add a missing '.' in the error message
Merge pull request #952 from GLolol/aka-2

Aka: add 'list' command & update listCommands override
plugins/__init__.py: remove some unused? imports
Topic: remove duplicate import
Topic: allow specifying a commalist of topic numbers in 'remove'
Merge pull request #972 from GLolol/topic-1

Topic: remove duplicate 'import re'
Merge pull request #971 from GLolol/plugin-init

plugins/__init__.py: remove some unused imports
Topic: switch 'remove' to many instead of commalist
Topic: add test for removing multiple topics
Merge pull request #975 from GLolol/topic-remove-commalist

Topic: in 'topic.remove', allow specifying multiple topic numbers to remove