[map] Preliminary implementation of union/branch/branch

Ignore-this: 2f175a0694142a26c61f24d1032265d6

darcs-hash:20130711143506-2809a-a4cdda6318775ddb409d7937f9c09934e212e9c9
[gsac] Test looking up second (present) key in a union

Ignore-this: e254c7ed4ebc09f081fc97526e0e0822

darcs-hash:20130711144015-2809a-a4d9c0dd64aae9db52482fdfadfc2057b61af87d
[map] Implement ordered.map.union when left key is > right key

Ignore-this: 2539b2d7fbd0cd4b436063e873d0d500

darcs-hash:20130711165745-2809a-2fe0b044962914f82d71226f3343eeeae3ac5dda
[map, set] Add credits

Ignore-this: d5748572a8a874d654d1e11af47af475

darcs-hash:20130711165907-2809a-3d01907489d97cb679b49bc1d0973370c9a19314
[gsac] Fill out gsac.gstype.kindcheck/app

Ignore-this: e924393ed79a9377fe17d4217cd2b9d8

darcs-hash:20130711181117-2809a-0c47a5995002a83806678968db1aba77e040f2be
[gsac] Implement parse tree for exponential kinds

Ignore-this: 569d51326a45a45da72cc95fd80a9c51

darcs-hash:20130711191908-821d0-d143913251f791459a6a016cb337ca6a61301bfc
[gsac] Add exp constructor to cgs.gskind.t

Ignore-this: 24681745f25c4e8dbbc6c8f872f8d3bd

darcs-hash:20130711211326-2809a-56d30e514577b4046af43d0826933598064eec56
[gsac] Translate exponential kinds to Core

Ignore-this: fcc475da9ccf5e3840f92702e134832e

darcs-hash:20130711211329-2809a-ff91234db08d42b995e8abe6a55bf650b8e20885
[gsac] Fill out gstype.kindcheck/app

Ignore-this: 4664c99e9cf7372f089e9505ea18e30c

darcs-hash:20130711211511-2809a-1890edf5db2624b67ed9a6d273c3e4727a1eecd0
[gsac] Fill out gsac.gstype.kindcheck/app

Ignore-this: 145fb1d2aef1051d0411d629eaaa1c96

darcs-hash:20130711221652-2809a-48513760469c2e8579440f1d34d85f510c5729cc
[gsac] Fill out gskind.upconvert/exp

Ignore-this: 7561eeaf93a0ab4093782e6e377f9250

darcs-hash:20130711222936-2809a-5cab2f8d7cee0fa8fb1f205baedbca4d87b85c28
[gsac] Fill out kindcheck/app

Ignore-this: 2293a33c6ac8438d3cb8d807694fb336

darcs-hash:20130711223218-2809a-e25b0cb4c1ab1ef7936a5e1a2a278fb55533c076
[gsac] Finish gskind.upconvert/exp

Ignore-this: 5e2fa853681b6ca9abd0fd603bc21f2d

darcs-hash:20130711223302-2809a-96a94d4c8598955ca658c20eaa83bd56e5e6fef9