Add a arrow symbol (->) to the lexer
Add a arrow symbol (->) to the lexer

Bug #368
Add a test for the arrow operator

Bug #386
Rename test function
When parsing type, expect a single '->' token
Rename byte_types to _byte_types

Bug #331
Merge pull request #387 from iankronquist/no-space-in-arrows-368

No space in arrows 368
Merge branch 'rename-byte-types'
Resolving merge conflict after latest commits to master
PEP 8 fixes for testlex.py