Import diff.Parser from https://github.com/abarth/codereview
Use sugar helpers in diff.Parser
Remove support for comments and drafts from diff.Parser
Remove async diff.Parser path, we'll add it back later
Put constants on the class in diff.Parser
Rename diff.Parser to DiffParser and remove anonymous wrapper.
Switch indent to 4 spaces
Now that we always parse diffs sync merge parseLine into parse
Fix up style of DiffParser and use sugar.
Parse the diff that comes back from PatchFile.loadDiff