Create parsing API, Lllex.parse
First version to compile with new parser
Fix usage string typo
Fix -no-cil flag
Parse instruction metadata

Still need to add instruction metadata to AST
Parse attribute group ids after calls
Fix parsing and printing of mdnodevector

These need to be comma separated instead of space separated.
First version to produce output with new parser
Fix some basicblock/label bugs
Fix bugs in llvm variable type inference
Bring the usage message up to date
Correct bug in phi elimination

Mergesort now compiles and runs
Handle type definitions (Vartyps) in type inference