ENH: add CMAKE_FILE_PATH, CMAKE_PROGRAM_PATH, CMAKE_LIBRARY_PATH, and search them first, PATH second, and last the paths listed in the FIND call

Fix: ApplicationInstallationDirectory was broken. Trailing /bin was stripped off. First it breaks all the apps relying on this method to find where the binary is installed (hello VV plugins ?), second this is completely hard-coded, there is no check, what about msdev path, bin/release, bin/debug, etc. If you need to remove whatever dir, just copy the result of this method to a buffer and strip it, thank you.

enh: add function to update a photo given a buffer, or a filename. Same as UpdatePhoto, but provides a way to load the picture directly if it is found

enh: add SeparatorMargin to put margin around the split. It's not up to the ui elements on left or right to provide the margin, it was up to the separator (otherwise margin gets added on the opposite side of the frames too, and it's ugly)

enh: add some basic interaction code (hook to VTK generic interactor), and basic reset/reset cam mode. Make Renderer/OverlayRenderer private to make sure Get/Set methods are used (subclass may replace those renderers with their own, but we want the code to still work)

enh/fix: add NoDecorate options, fix computation of size of dialog if it has not been mapped, clean a little