…bda should be interpolated. This breaks one of the current tests of lambdas (higher order sections), as it asumes that the result is not interpolated. I updated the test so that it pass.

…d calls. All metods in a name path should be called in the context of their containing object. In current mustache.js only the last name in a path is called and it is called in the context of the name lookup rather than of its object. This patch breaks the current behaviour, so I provided an extra context parameter to make it easier to update programs using the current function context behaviour. A breaking test is fixed and there are new tests for method calls etc.

Updated documentation for the new method interpolation behavior.