Added jstimezonedetect (jstz.js) library

131 followers on BitBucket: https://bitbucket.org/pellepim/jstimezonedetect

Source taken from: https://bitbucket.org/pellepim/jstimezonedetect/src/0aba564fe816811753578e36f3051f24644fc5d8/jstz.js

minified: https://bitbucket.org/pellepim/jstimezonedetect/src/0aba564fe816811753578e36f3051f24644fc5d8/jstz.min.js