Fixed issue. When ranging multiple beacons(with the same UUID), only one beacon is detected.
remove unnecessary code
Merge pull request #91 from jccode/multiple_beacons_issue

Fixed multiple beacons issue
Replaced hardcoded value true with parameter runInBackground
Added check of null pluginResult that caused app to hang under certain conditions
Added string quotes to JavaScript log message (caused JS syntax error when missing)
Replaced deprecated method call on iOS