Fix inconsistency in defining global mustache object.
Fix inconsistency in defining global mustache object.

janl/mustache.js,aaron-goshine/mustache.js,phillipj/mustache.js,aaron-goshine/mustache.js,janl/mustache.js,phillipj/mustache.js,ivantcholakov/mustache.js,ivantcholakov/mustache.js,janl/mustache.js,wjbryant/mustache.js,ivantcholakov/mustache.js,wjbryant/mustache.js,phillipj/mustache.js,janl/mustache.js,phillipj/mustache.js,phillipj/mustache.js,ivantcholakov/mustache.js,aaron-goshine/mustache.js,aaron-goshine/mustache.js,wjbryant/mustache.js,janl/mustache.js,wjbryant/mustache.js