Fix crash on startup on Linux

Fix originally provided by gliptic.
Don't add ".dat" to liero.dat when already present
Add Replays and Profiles to .gitignore
Add -Wall to makefiles
Fix ordering in constructors
Removed unused variables
Fixed signed/unsigned comparisons
Merge pull request #4 from ahockersten/ahockersten/bugfixes_etc

Fix some smaller bugs and refactor away some warnings