Added basic JS tests for OLMapWidget.js

Thanks Trey Hunner for cleaning the initial patch and Tim Graham for
the review.

js_tests/gis/mapwidget.test.js

@@ -0,0 +1,46 @@
+/* global module, test, MapWidget */
+/* eslint global-strict: 0, strict: 0 */
+'use strict';
+
+module('gis.OLMapWidget');
+
+test('MapWidget.featureAdded', function(assert) {
+    var options = {id: 'id_point', map_id: 'id_point_map', geom_name: 'Point'};
+    var widget = new MapWidget(options);
+    assert.equal(widget.layers.vector.features.length, 1);
+    assert.equal(
+        widget.layers.vector.features[0].geometry.toString(),
+        'POINT(7.8177 47.397)',
+        'Point addded to vector layer'
+    );
+});
+
+test('MapWidget.map_srid', function(assert) {
+    var options = {id: 'id_point', map_id: 'id_point_map', geom_name: 'Point'};
+    var widget = new MapWidget(options);
+    assert.equal(widget.options.map_srid, 4326, 'SRID 4326');
+});
+
+test('MapWidget.defaultCenter', function(assert) {
+    var options = {id: 'id_point', map_id: 'id_point_map', geom_name: 'Point'};
+    var widget = new MapWidget(options);
+    assert.equal(widget.defaultCenter().toString(), 'lon=0,lat=0', 'Default center at 0, 0');
+    options.default_lat = 47.08;
+    options.default_lon = 6.81;
+    widget = new MapWidget(options);
+    assert.equal(
+        widget.defaultCenter().toString(),
+        'lon=6.81,lat=47.08',
+        'Default center at 6.81, 47.08'
+    );
+});
+
+test('MapWidget.getControls', function(assert) {
+    var options = {id: 'id_point', map_id: 'id_point_map', geom_name: 'Point'};
+    var widget = new MapWidget(options);
+    widget.getControls(widget.layers.vector);
+    assert.equal(widget.controls.length, 3);
+    assert.equal(widget.controls[0].displayClass, 'olControlNavigation', 'Navigation control');
+    assert.equal(widget.controls[1].displayClass, 'olControlDrawFeaturePoint', 'Draw control');
+    assert.equal(widget.controls[2].displayClass, 'olControlModifyFeature', 'Modify control');
+});