a borderless window alternative

this pr is about changing the current borderless behavior

why?

- we got many issues with our current solution, because we use ```AllowsTransparency="True"``` for the ```MetroWindow```
- ```AllowsTransparency="True"``` breaks the ClearTypeHint mechanism
- with ```AllowsTransparency="True"``` no WinForms/WebBrowser works

so what is the benefit and what is changed

- no more ```AllowsTransparency="True"```
- use shell WindowChrome for custom window
- WinForms/WebBrowser should work (browser can be tested in demo app)
- ClearTypeHint works
- the Window animation is moved to the content and not for the hole window

i hope this solution works even better the old one