Declarations and definitions are now separated.
Added explicit int3(si32) c-tor.
Operators like += now return reference to object.
Operator != has now own implementation.
Added dist2SQ for optimization proposes.
areNeighbours now uses dist2SQ
Removed unnecessary comments
int3 dist2d microoptimization
Fixed small error in nearest town finding algorithm.
All inline functions are now part of definition.
Removed hardcoded value
Merge pull request #15 from karol57/develop

Updated int3 class and fixed small error.