added time parameter to SourceImageWMS (#52)

Some WMS have a time dimension as well. This PR adds this functionality as an optional string prop to the SourceImageWMS component.

Author: meister-eder

src/components/sources/SourceImageWMS.vue

@@ -32,7 +32,8 @@ export default {
                 ...properties,
                 params: {
                     'LAYERS': props.layers,
-                    'STYLES': props.styles
+                    'STYLES': props.styles,
+                    'TIME': props.time
                     },
                 projection: typeof properties.projection == "string" ? properties.projection : new Projection({
                     ...properties.projection
@@ -106,6 +107,9 @@ export default {
             type: [String,Array],
             default: ''
         },
+        time: {
+            type: String
+        },
         ratio: {
             type: Number,
             default: 1