Clean up specs related to srp user testing - need another approach.
Update xib files for xcode5 in Example app.
DependencyProvider will not provide srp user (for now).
[#34] Major cleanup of srp and srp related MeteorClient.

- Don't attempt login if login is already in progress.
- Move SRPUser struct to header
- Fix memory leaks
- Simplify and clean code