FPS counter cleanup

- Isolate it into it's own namespace
- Shorten function names, the namespace self-documents.
- Just use the std I/O, we can just write directly to the stream for
  logging.
Add support for 2 memory cards for movies.
Merge pull request #550 from RachelBryk/movie-mc2

Add support for 2 memory cards for movies.
Clean up string handling in Movie.cpp
Merge pull request #551 from lioncash/movie

Clean up string handling in Movie.cpp
Fix a type-conversion warning in Movie.cpp

Fixes a C4800 warning. 'int' : forcing value to bool 'true' or 'false'
(performance warning)
Merge pull request #552 from lioncash/warning

Fix a type-conversion warning in Movie.cpp
Merge pull request #549 from lioncash/fps

FPS counter cleanup
Old versions of libavcodec should work again.
Merge branch 'master' of https://github.com/dolphin-emu/dolphin into fix-compilation-on-debian-8-with-libavcodec
Fixing a copy-paste error