added occurs check
added some implementations of search
added more implementation of proof search
finished the proof search for foralls, exists might be broken
added occurs checks and gvar-uvar-depend check
added dependent pairs for the purpose of typing existential quantification
fixed a bug
removed the pair stuff since it was not correct
I now have the correct implementation of existentials in type checking, just need to add it in proof search and make a pretty printer
added more inference for existential quantifier
finished proof search terms for existential quantification