Add option to SimpleMC to upgrade to latest version

[TheHacker66]

Would be awesome to have an option to upgrade directly from simpleMC instead of having to run pip install simpleMediaCenter --upgrade every time.

[ingwinlu]

hi,

sadly this is not a viable idea for me because:

• pip is just one way of keeping the program up to date
• there are differences between pip installations (pyenv, --user, ...) which further influence which kind of permissions the --upgrade switch would need
• viability only during the development phase

you are probably better of with a shell script which emulates the behaviour you want