chrome.bluetooth: enable [start|stop]Discovery and register events once only
Merge pull request #421 from oahziur/ble-ios-improvement

chrome.bluetooth and chrome.bluetoothLowEnergy changes
CB-7980 Set BUILD_MULTIPLE_APKS only if webview != system

When using system webview, there is no need to build multiple APKs.

See https://issues.apache.org/jira/browse/CB-7980
CB-7980 Set min/target SDK version via manifest

minSdkVersion was previously set in post-prepare.
Now it's copied from manifest to config.xml in pre-prepare.
cordova-lib then copies it from config.xml to AndroidManifest.xml
Fix #420 - cca upgrade wasn't updating all plugins
Allow versions with 4 dot separated numbers

Fixes #401

Any version names with 1 to 4 dot separated numbers are now allowed. All of
the following are valid: 0.0.1.0, 2, 42, 3.14, 1.2.3

For version code calculation only the first 3 numbers will be considered the
fourth is ignored. If there are less than three numbers, extra .0 or .0.0 is
appended (this is done in cordova-lib).

Also removed an old workaround for a cordova-lib issue that will be in with the
next release.
Update cordova-android, cordova-ios and cordova-crosswalk-engine to support whitelist plugins
Update chrome-navigation plugin to be a new-style whitelist plugin