- Add comments (precondition, postcondition) to all functions in UserController, and GoogleController
- Remove getAvailable() old function no longer use

*** LabCrasher ***
- Modify getAvailability to take into account when calling for future date.
Merge branch 'master' of https://github.com/leovander/CorrelaterBackEnd

# By Israel Torres
# Via Israel Torres
* 'master' of https://github.com/leovander/CorrelaterBackEnd:
  Update readme.md
  Update readme.md