[cage] add makefile codas also to the Defines.mak
[build] opsrenumber.pl is long gone

remove the make target
[imcc] fix crash with -d8 DEBUG_IMC dump_instructions
[core] Optimize utf8_substr. do not use utf8 iterator

Use a new utf8_offset function instead. This can be optimized
further if we can guarantee word alignment of the buffers.
Add a special utf8 vtable method for substr.
This is a hot item for perl6, see GH #1097

Do not export the Parrot_utf8skip table anymore, not used
by parrot, nqp, perl6.
[test] add testcase for double-quoted lex names GH #1095

in perl6 the correctly double-quoted .lex "foo\\o", $P3 name fails to work.
see https://rt.perl.org/Public/Bug/Display.html?id=116643
this might be caused by the switch from globals to lexicals, as this statement
is now enclosed in a block.

in parrot the binary character \0 causes problems in lexnames with roundtrips.
[test] Added LexInfo.declare_lex_preg and more imcc/syn/clash.t tests

For GH #1095

global names do work fine, only lexicals not.
Note I do not know how to reliable get the correct target register index for
declare_lex_preg in pure pir, and how to initialize it.
Setting it crashes the ctx.
[test] add testcase for immc parser bug even with globals

Also updated [GH #1095]
[test] just clarifying comments about the parser
WIP development only: add -t8 flag, unescape in mk_const

see https://github.com/parrot/parrot/issues/1095#issuecomment-58470471
WIP mk_const and str_unescape: skip "
WIP: fixed the tests, but broke parrot

allow and handle now empty strings im imcc, fix
quoted sub names
different string escape policy now

die now with unknown escape sequences A-Za-z,
but allow quoting of special non-word chars, like
\", \[, \}
imcc encodings: fix unicode encoded constants
[imcc] fix .sub name last char
[imcc] fix -d8 dump_instructions, fix double unescaping

string_from_reg may not unescape the const again. fixes t/op/basic_6.pasm
change t/op/basic_9.pasm to catch the new Unknown escape sequence \i in Parrot fl\ies
Add throw_illegal_escape_char, add arg to throw_illegal_escape

Harmonize Illegal escape sequence \\%c in %Ss and
Illegal escape sequence %Ss error messages.
Also allow \? \

Note that the C standard requires such "invalid" escape sequences
to be diagnosed i.e., the compiler must print an error message.
[imcc] fix U type in sub fixup

Honor mk_const Slp, do not change S to U when called a 2nd time as S
with already stripped quotes.

Change -t8 private trace flag to -d2 proper imcc flag for mk_const tracking
Add more debugging verboseness.
[imcc] the plot thickens. pass the ghash|0 to _mk_const

do not unescape binary strings containing 0
[imcc] 2 more -t8 leftovers over to -d2

Note that currently string_from_reg is the best place to resolve
encoded U strings, as registers store them the same way as in symreg constants.
But we should optimimze that to be more efficient, see GH #1097
[imcc] represent constants with \0 as fixed_8:"\x00"