jshintrc: allow true and false as values for jshintrc config
jshintrc: allow true and false as values for jshintrc config

in order to allow nested jshintrc files that will be picket up automatically by jshint
or no jshint files at all, for the case that options are being set in the grunt
configuration directly

Jimdo/grunt-jquery-toolbox,Jimdo/grunt-angular-toolbox,Jimdo/grunt-angular-toolbox,Jimdo/grunt-jquery-toolbox