UI: Add function to find default video save path

On windows this will return the documents\video directory, but on
linux/mac it'll just return $HOME for the time being because I don't
know if there really are any other appropriate adequate paths to use.
Perhaps someone else can be willing to fill this in if they wish.
UI: Add function to generate time/date filenames
UI: Add FLV file output (sharing encoders)

Implement the 'file path' in output settings, and implement the 'start
recording' button, though for the time being I'm just going to make it
use a directory rather than allow custom file names.

This file output will actually share the video and audio encoder with
the stream.

I don't really know what to do about MP4 -- I don't really like the idea
of saving directly in the program, if you do and the program crashes,
that MP4 file is lost.  I'm contemplating making some sort of mp4 output
process stub.  So no MP4 file output for the time being.

If you need MP4, just remux it with FFmpeg:

ffmpeg -i flv_file.flv -acodec copy -vcodec copy mp4_file.mp4
Update core to 0.2.4
libobs:  Move API version info to obs-config.h

This way it doesn't interfere with any actual relevant commits related
to obs.h.
Fix packet/frame counter for pulseaudio plugin

Reset the counters when the recording is stopped.
Fix requested latency for pulseaudio plugin

When the PA_STREAM_ADJUST_LATENCY flag is passed, pulse will interpret
the fragsize attribute as a literal targeted latency.
Remove pa timestamps option from pulseaudio plugin

Due to desync issues with the pa timestamps, os ones are
now the only option.
UI:  Fix string conversion bug

Parameter two of os_wcs_to_utf8 is how many characters to convert, not
how big the buffer is.
Add dst_size parameter to character conv funcs

Character conversion functions did not previously ask for a maximum
buffer size for their 'dst' parameter, it's unsafe to assume some given
destination buffer may have enough size to accommodate a conversion.
Fix a few warnings on windows
Fix ffmpeg/x264 find modules according to cmake find module naming conventions
Add Libfdk find module
Merge pull request #92 from fryshorts/pulse-input

A few smaller fixes for the pulseaudio plugin
Add Japanese translation

Add Japanese translation
Added Italian locale

The English locale file was a bit vague and I didn't have time to delve deep into the UI source code, so it's a bit generic.
Add libfdk encoder
Make obs-ffmpeg aac encoder output which encoder is beeing used
Merge pull request #93 from BtbN/fdk

Add libfdk_aac encoder module
Merge pull request #95 from shousa/master

Add Japanese translation