if we find them. (Avoid dropping the first frame).

* ALL: bumped version number to 0.7.2.

* modules/gui/wxwindows/menus.cpp: release the wxMutexGui lock before triggering object var callbacks.

    + Use the svlc shortcut for skins 2, too.

* modules/gui/wxwindows/open.cpp: simplified a string (sorry for the translations) because it was making the open dialog way too big.

* added an open button

- capture filter is more compatible with ICaptureGraphBuilder2
- some code cleanups especially when dealing with media types

- ordered device supported media types using an arbitrary fourcc preference priority before passing them to capture filter 
- removed assumption where YUY2 chroma was considered identical to UYVY

   a help string

* wxwindows/*: a few cleanup fixes.