[GH #1075] find_codepoint namealias

add a tools/build/namealias_c.pl to manually cleanup the generated
gperf c file for inline, C++ compat and codingstd_tests.

add Parrot_str_internal_find_codepoint to src/string/encoding.c
(not namealias.c because headerizer doesn't like namealias_c.in)

use that also for the non-ICU codepath, so that at least some names are
found. This can be used later to add all names to namealias for non-ICU builds.

remove inline from namealias. This doesn't need to be fast, just small.

fixup some weird codingstd tests for namealias. podchecker passes but Pod::Simple not.
c_parens.t misparses namealias_c.in as functions

make headerizer and bootstrap-ops.
Makefile: remove special @cc_shared@ as it included in $(CFLAGS) now