Added char-based range functions. Range behaviour now matches Twig. Per #188
Had to go a different route for #188. Single range function handles all required cases
Fixed #152. JTwig equivalence evaluation is now loose, conforming to Twig's way of doing things.
Added min and max functions per #196, and a supporting ObjectUtils class which manages comparisons PHP-style.
I bungled my last commit. This fixes that.
Merge branch 'fix-equivalency-checking' of github-personal:thomas-p-wilson/jtwig
Merge branch 'fix-range-chars' of github-personal:thomas-p-wilson/jtwig