.hgignore
Traits class + named parameters for MinMeanCycle (#179)
 - Add a Traits class defining LargeValue, Tolerance, Path types.
   LargeValue is used for internal computations, it is 'long long'
   if the length type is integer, otherwise it is 'double'.
 - Add named template parameters for LargeValue and Path types.
 - Improve numerical stability: remove divisions from the internal
   computations. If the arc lengths are integers, then all used
   values are integers (except for the cycleMean() query function,
   of course).