[Freeorion-programmers] Patch for GG to get FO to compile under GCC

[Dennis B. <de...@fs...>]

Hi Zach, hi list.

The lastest update to GG broke the GCC build; it seems like GCC does not 
store inline function information in object files, and thus cannot link 
the final executable. I've moved the definition of GGClr operator== into 
the header-file. Patch to GG is attached.

Can I commit these changes?