[examples/*.rc] Explicitly specify resource script language.

We use LANG_NEUTRAL for images and manifests, and LANG_ENGLISH
for dialogs, menus and other language-specific resources.
[IMGVIEW] Many fixes of IStream implementation.
[IMGVIEW] Improve comments.
compat.h: Improve mc_clz().
tests/test_build.c: Fix gcc warnings.
src/guid.c: Removed. Link with uuid.a instead.
[Build] Require CMake 3.1 or newer.

Also remove hacks workarounding CMake 3.0 bug, which prevented to
propagate options to RC.EXE with Visual Studio generators.
[Test] Fix typo.
[Test] Rename expssym_test() to export_test().
[DSA] Support for "compact" DSA.

Compact DSA does not pre-allocate larger buffer capacity then actually
needed.
[Viewlist] Re-implement on top of a compact DSA instead of a linked list.
[Test] Update cutest.h from upstream.
[HTML, IMGVIEW] Use COM interface wrapper macros...

... instead of twiddling with IFACE_PTR->Vtbl->METHOD_NAME.