set default template parameter to void
Merge pull request #21 from kariya-mitsuru/less_equal

[functional.less_equal] set default template parameter to void
fix minmax_element
Merge pull request #22 from kariya-mitsuru/minmax

[algorithm.minmax_element] fix minmax_element(max part) etc.
fix minmax_element
fix various
fix min, max, minmax
Merge branch 'minorfix' of github.com:kariya-mitsuru/Sprout into minorfix

Conflicts:
	sprout/algorithm/minmax_element.hpp