[WIP] Implement #lolcode

[CodaFi]

This is the corresponding implementation of #lolcode.

We are still working through the particulars of loops and switches because the spec is quite vague on some points, hence WIP.

Also, while implementing this we realized that LOLCode reserves A, Z, O, and R as keywords - and stdlib uses those as generic argument names. It also reserves NO, so I took the opportunity to just remove that little error we make for ObjC NO. YAGNI, or something.

[CodaFi]

Let's see what horrors await

@swift-ci please smoke test

[harlanhaskins]

@CodaFi and I are thrilled to bring forward this groundbreaking feature on such an important day.

[jrose-apple]

It seems unfortunate that the error messages for LOLCODE (sic) are in the same formal tone as the ones for the rest of the compiler. To make this part of the language more compelling, I suggest having form follow…something…and taking inspiration from the syntax itself:

ERROR(expected_of_lolcode_builtin,PointsToFirstBadToken,
      "ABSENCE OF 'OF" -> NO COMPILER LOVE", ())

ERROR(statement_lolcode_same_line_without_comma,none,
      "WHY CANT I HOLD ALL THESE STATMENTS", ())
ERROR(statement_lolcode_no_yarly,none,
      "DONT LEAV ME HANGIN", ())
ERROR(statement_lolcode_aggressive_orly,none,
      "Q U E S T I O N   E V E R Y T H I N G", ())