[clang-format] first stab at a .clang-format file that matches the existing style

Not enabled by default, but if you want to use this one for now while
things are stabilized feel free. Going to move off astyle since this
seems to be superior now (wasn't always).

Also switched scripts/codestyle to use clang-format

scripts/codestyle

@@ -1,13 +1,5 @@
 #!/bin/sh
 
-# formatting script using the astyle tool
-# use -A2 (java style braces)
-# 4 space indents, convert tabs to spaces
-#
-# switches documented at http://astyle.sourceforge.net/astyle.html
-#
-# optional switches to note:
-# --add-braces will add { } for every conditional, including one liners
-
-astyle -A2 --align-pointer=name --indent=spaces=4 --indent-switches \
-    --keep-one-line-blocks --pad-header --convert-tabs $@
+# formatting script using clang-format.
+# the format is described in .clang-format file at the root of the project.
+clang-format --verbose -i $@