[add eq to grin node analyze type
John Meacham <john@repetae.net>**20120118055621
 Ignore-this: 1d32b1c2152908ff8613b0bc50701cd3
] hunk ./src/Grin/NodeAnalyze.hs 56
+    eq    (N x y) (N x' y') = eq x x' && eq y y'
+    showFixable n = show n