Gallery App: added init. readme for qml developers

app/qmlV2/readme.txt

@@ -0,0 +1,27 @@
+Rules for a Qml [new design] developers
+- main folder input/app/qmlV2/
+- all components, pages, map items, ... in its subfolder
+- all items begins MM, for example MMButton
+- using required key before property, if it makes sense
+- using property alias, if it makes sense
+- using qmlfmt tool for Qml formatting, see qmltool section
+- using GalleryApp for creating/updating qml files, see GalleryApp section
+
+qmltool
+- git clone https://github.com/jesperhh/qmlfmt.git
+- cd qmlfmt 
+- git submodule update --init qt-creator
+- mkdir build  
+- cd build
+- export Qt6_DIR="/your_path/Qt/6.5.2/macos/lib/cmake/Qt6"
+- export Qt6GuiTools_DIR="/your_path/Qt/6.5.2/macos/lib/cmake/Qt6GuiTools"
+- export Qt6Test_DIR="/your_path/Qt/6.5.2/macos/lib/cmake/Qt6Test" 
+- cmake ..
+- make
+- ./qmlfmt -wi2 path_to_qml_dir
+
+GalleryApp
+- located in input/GalleryApp/
+- uses qml files from input/app/qmlV2/
+- as wrapper for qml files see input/GalleryApp/qml/
+- works hot reload (tested on Mac), if any problem see script in HotReload class