Refactor: libcrmcommon: Add curses_internal.h.

This moves all the curses-related header inclusion and defines out of
lib/pengine/unpack.h into its own internal header file. As the
formatted output code expands to include curses support, it will be
useful to have this new header.

status_print and status_printw could potentially stay in lib/pengine as
that is the only place they are used, but they're curses related so I've
chosen to keep them all together. Note those macros assume global
variables.