Opening a demo via client parameters

[Kabcorp]

To read a demo, we have actually two ways:

1. Navigating into the defrag menu
2. Using a third party software that copy the demo into a temporary game/demos/ folder

Feature request example:

odfe.exe "D:\foo\bar\mydemo.dm_68"
odfe "/home/foo/bar/mydemo.dm_68"

It will be much more efficient to start demos a from a file browser by simply open dm_68 files with the client binary

Making the ability to read a demo away from the Quake 3 folder
or
Copying the demo temporary into defrag/demos/tmp...

Thank you.