Retain literal values when translating, use Integer instead of Int

typechecker/src/Initial.hs

typechecker/src/Parser.hs

typechecker/src/Tc/Gen/Expr.hs

typechecker/src/Tc/Solver.hs

typechecker/src/Term.hs

typechecker/src/Type.hs

typechecker/test/cases/parser/leftPlusTwo-parser.output

typechecker/test/cases/parser/plusPlus-parser.output

typechecker/test/cases/should-fail/constFail-infer.output

typechecker/test/cases/should-fail/notTo3-infer.output

typechecker/test/cases/should-fail/plus3ToBool-infer.output

typechecker/test/cases/should-typecheck/Just-3-tuple-pb.hs

...hecker/test/cases/should-typecheck/Just-3-tuple-pb.output

typechecker/test/cases/should-typecheck/JustXfmap.output

typechecker/test/cases/should-typecheck/absMaybe.hs

typechecker/test/cases/should-typecheck/absMaybe.output

typechecker/test/cases/should-typecheck/absMaybeMaybe.hs

typechecker/test/cases/should-typecheck/absMaybeMaybe.output

typechecker/test/cases/should-typecheck/apply-infer.output

...est/cases/should-typecheck/ifTrueThenPlusTwo-infer.output