sys.argv is now read-only.
Added the Python power operator (**).
Added support for: for line in sys.stdin (NSFileHandle extension). Added sys.argv tests.
Added time.time()
Removed redundant function definition - redundant since Int is automatically converted to Double.
Added dict.get(key).
Merge branch 'master' of https://github.com/practicalswift/Pythonic.swift

# By practicalswift
# Via practicalswift
* 'master' of https://github.com/practicalswift/Pythonic.swift:
  Added dict.get(key).
  Removed redundant function definition - redundant since Int is automatically converted to Double.
  Added time.time()
  Added support for: for line in sys.stdin (NSFileHandle extension). Added sys.argv tests.
  Added the Python power operator (**).
  sys.argv is now read-only.