Proper release of GPU cache thanks @Isalia20

Also close #142 issue between mismatch of version 0.2.7 and the pypi distribution.

Fix an issue bad naming of variable. A thank you to @ya0guang

Update readme with how to use backgroundremover as a library and made a pull request fixing the circular imports for it to work correctly. A thank you to @ahmad88me

Fix an issue with moviepy requirments.

Take out shlex, put commands from subprocess into list before.

Let ffmpeg log alphamerge to see if helps shine 0kb error

Closes issue #84

Fixes #78 and #80

Fix issue #18 for Mac users
Fix issue with inputs of videos with special characters
Fix spelling issues in read me

Fix issues with windows.
Fix issues with download files from google vs github.
Fix issue with remove background from local video and overlay it over an image
Fix issue with frame_rate detection on some videos

Fix issue with u2net import, where would re download existing libraries on system.

Fix relative import issue