Switch user agent detector. Add tests.

Author: allanca

CHANGELOG.md

@@ -1,6 +1,8 @@
 ## Unreleased
 
 * Use gzipped version of the library by default. If you still need the uncompressed version, remove ".gz" from the script url in your integration snippet.
+* Upgrade user agent parser for browser detection to keep up-to-date with browser updates.
+* Fix bug where Android browsers were reported as Safari on Linux.
 
 ## 2.1.0 (March 23, 2015)