Remove and readd onMapChange in onStart/onStop

[cammace]

Closes #363

When the location layer plugin's disabled, we remove the onMapChange listener.

[LukasPaczos]

Won't this one unregister the listener during style switch resulting in disabling the location layer? See

mapbox-plugins-android/plugin-locationlayer/src/main/java/com/mapbox/mapboxsdk/plugins/locationlayer/LocationLayerPlugin.java

Lines 632 to 641 in 86a6708

	public void onMapChanged(int change) {
	if (change == MapView.WILL_START_LOADING_MAP) {
	onStop();
	} else if (change == MapView.DID_FINISH_LOADING_STYLE) {
	locationLayer.initializeComponents(options);
	locationLayerCamera.initializeOptions(options);
	setRenderMode(locationLayer.getRenderMode());
	onStart();
	}
	}

.

[cammace]

I've added separate onLocationLayerStop and start methods to extract the location layer lifecycle events from the activities which the plugin's contained within. This means when onMapChange gets called we don't remove the listener.

[LukasPaczos]

If the plugin is disabled and we change the style this line will draw the puck in the last location even though the plugin is disabled. Could you address it in this PR as well?

[cammace]

Yes, want to make this clear that this is a bug that is in master though, not something I introduced in this PR...

[cammace]

After looking into this, I'm not finding a solution to this fix. Will open a ticket and revisit in a separate PR.

[cammace]

#515