* Cleaned up code:

* Cleaned up code:
  - no more passing around a string pointer to set errors
  - no more returning booleans and checking for errors, we use C++ exceptions
* Broke functionality into 2 new classes, one reads from file, one from a stream
* Implemented lazy function streaming - the parser can read in a function at-a-time

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8671 91177308-0d34-0410-b5e6-96231b3b80d8