[Bug 915686] The great showfor rewrite of 2013.

http://khanaas.com/kirk/showfor

Rebeca says yes. Verdi says yes. I say yes. This is ready to go. Lets do this!

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This isn't ready for r? yet, but I would love some f? on it, if anyone has time. I think that this is feature complete. Tomorrow I'm going to read through this entire diff and do a self-r?, but I haven't done that yet.

I'm putting this up now mainly because I think it is ready to see the light of day, even if it isn't 100% done. I realize that a 38 file, +1462/-1286 patch is going to take a long time to process, so I want to get it out here sooner rather than later.

I know that Rebecca Billings is going to help with QAing this (I'm meeting with her and Kadir tomorrow to talk about that), and this bug is [needsverify], so it will (hopefully) get tested by the other side of SUMO too.

Reviewing tip: Don't try and read the diffs for showfor.js, or showfortests.js. I completely rewrote those files, and the diff is just hard to read.