add char name lookup aliases (LF,FF,CR and NEL)

The Perl 6 spec and therefore roast says that e.g. \c[LF] is identical to
\c[LINE FEED (LF)]. MoarVM already got a similar patch:
https://github.com/MoarVM/MoarVM/commit/339d547cdd0bec45e2ac3f6d97fb6b9b77bdfce0
And it would be nice if Parrot would get this ability, otherwise we would
have to do it in a rather slowish way in nqp.

Closes GH #1085.
Signed-off-by: Reini Urban <rurban@cpanel.net>
[test] fix test number in t/library/pg.t
[native_pbc] update fingerprints

with perl tools/dev/pbc_header.pl --update-fingerprint t/native_pbc/*.pbc
(should be done before every release, not after)
[docs] Updated StringHandle.readall and FileHandle.readall docs

They read just the rest of the buffer if tell > 0. [GH #1084]
This is not what you would expect, but perl6 wanted it this way.
See GH #930 for the discussion.
ChangeLog: update
Revert "[test] fix test number in t/library/pg.t"

This reverts commit 9abb27dd6f14bf1fafc312b747a77b1b4c9ae5a5.
Need to find out why on my system it only runs 40 tests
ChangeLog: revert t/library/pg.t change
[test] library/pg.t: handle plan for the 3 error cases

Some smokers run 43, some 40 tests.
Use no_plan and handle the earlier exits properly.
3 error cases: no libpg.so, service stopped, no nci thunks.
[pcc] inline pcc_add_invocant and its attr accessor
[pcc] temporarily add two hand-optimized callcontext pmc files

see gh #1083
[pcc] more hand-edited changes GH #1083
[pcc] actually use now the direct methods GH #1083

and do not use the CallContext vtable methods anymore.
also inline one Continuation_set_pointer call.

all tests still passing, 2.98% faster.