Updated validation checks & comments for the Gamedata "class".
Updated replayer's src/README.md
Added gtk2_player/src/BROWSING.md with sources info & coding style
Updated gtk2_player/src/README.md file
Updated README.md file
Removed erroneous links from README.md and src/README.md
Merge pull request #15 from migf1/dev_gtk2_replayer

Dev gtk2 replayer