C++ Mode: Handle new keywords static_cast, etc., wrt angle brackets

C++ Mode: Handle new keywords static_cast, etc., wrt angle brackets

* lisp/progmodes/cc-langs.el (c-<>-arglist-kwds): Add const_cast,
dynamic_cast, reinterpret_cast and static_cast into this lang const.

* lisp/progmodes/cc-engine.el (c-clear-<-pair-props, c-clear->-pair-props)
(c-clear-<-pair-props-if-match-after, c-clear->-pair-props-if-match-before)
(c-forward-<>-arglist-recur):
Invalidate caches with c-trunctate-lit-pos-cache.
(c-forward-<>-arglist-recur): If in a matching <...> expression, the < has a
syntax-table property, but the > not, remove that property.