Fixing a crash when !pixiv is not passed search terms

Line #44's `arr === null && term` evaluates to false due to `term` (`''`) evaluating to false. Subsequently line #47 crashes with `TypeError: Cannot read property '4' of null`.
Merge pull request #32 from HigherFive/pixiv_fix

Fix a crash when !pixiv is not passed search terms
Remove space which still made it crash
Better handling of !choice and !seen with no terms
Merge pull request #34 from HigherFive/various_fixes

Better handling of !choice and !seen with no terms
Making bot.js trim the messages before passing them to the !commands
Removing unnecessary trims from command definitions.
Merging pet.js and pat.js into the generalized emote.js
Adding !hug(s) and !thank(s) commands to emote.js
Tweaking a bit to make non-recorded emotes possible.
Merge pull request #35 from HigherFive/emotePlugin

Adding emote.js plugin