QAD::Map:

* add MapViewTileProviderBase - base class for tile server provider
 * migrate OSM to new class
 * add MapTiler provider
 * add offlineMode for MapView

libs/map/mapview_tile_provider_base.cpp

@@ -0,0 +1,13 @@
+#include "mapview_tile_provider_base.h"
+
+
+void MapViewTileProviderBase::setParameters(const PIValueTree & vt) {
+	parameters.applyValues(vt);
+	applyParameters();
+}
+
+
+void MapViewTileProviderBase::initParameters(const PIValueTree & vt) {
+	parameters = vt;
+	applyParameters();
+}