Merge branch 'rurban/socket-gh909'
Add api.yaml entry for GH #909 Socket.read(>512)
Edit last api.yaml note, wrong ending single quote
[GH #641] Fix wrong PCCMETHOD line-directives (only .c)

PCCMETHOD only emits .c level lines, no PMC level ones. This generates now
proper directives for all _nci_ methods.
[codingstd] Add missing ChangeLog lines, fix socket.pmc line lengths
[GH #921] Fix tabs in src/dynpmc/Rules.mak cygwin/hpux

These missing tabs caused to miss the addgenerated lines for dynpmc libs.
[GH #921] cygwin Fix Could not create //usr/local/share/parrot/4.11.0-devel/MANIFEST

catdir with "" creates //.
[GH #922] addgenerated dynpmc headers in make, not pmc2c

rakudo and nqp do not have to clean a generated MANIFEST.generated.
[GH #893] add test for threaded say, mixup with \n

Test that for each say a \n is printed per thread.
Test it on a multi-core machine with

    watch prove -v t/op/say.t
[GH #893] improve concurrent say. concat with \n, then puts

Provide better atomicity with threads. To avoid mixing strings with
newlines in most cases. This is not foolproof of course.
concat only if it will not extend the already allocated buffer to
avoid copying.
make bootstrap-ops for say
[GH #893] Refactor better atomic say op: test for 80% success, concat if the buflen < 80

Since even SREGs are constant, Parrot_str_concat will always create a copy. So allow small cheap copies.
Merge branch 'rurban/threaded-say-gh893'
[codingstd] cuddled else in t/op/say.t
[GH #907] skip task.t until rurban/task.t-gh907 is merged
add t/stress/threads.t for GH #880 and GH #875
[spec] Update the socket doc for read and recv, to clarify our changed POSIX like behaviour

Before the high-level read() returned the wanted amount of bytes.
Now it behaves the same as recv().
We need to add a setsockopt(optname, optvalue) method.