Add FFMpegLoader.java

This class will load the ffmpeg executable from the jar file and then
extract it to be used by rest of the program
Add ffmpeg to project's dictionary :+1:
Renamed ffmpeg.exe to ffmpeg, so ignoring it.
Add code to create ffmpeg executable

On startup, the ffmpeg executable will be created.
Add a tiny comment
Add code to extract ffmpeg executable :smile:

No messy hardcoding of ffmpeg location. Now, ffmpeg executable will be
stored in app's .jar and then extracted temporarily to the %TEMP%
folder.
FIle will be deleted in exit ;)
Merge pull request #6 from cshubhamrao/ffmpegLoader

Add feature to load ffmpeg executable a runtime