Fix extra tab in GPL headers
|Reported by:||salty-horse||Owned by:||dreammaster|
Some of the source files (268 in number) have a tab in the GPL license text: "FOR A PARTICULAR PURPOSE.\t See the"
This is inconsistent with other files and with the "How to Apply These Terms to Your New Programs" section of the GPL.
The patch converts those tabs to spaces. It also fixes the indentation that engines/gob/game_v2.cpp has for the GPL header.
Ticket imported from: #1864454. Ticket imported from: patches/875.