chg: port commit 7e0ad82 from master to spielwiese

commit hash in master: 7e0ad82686aab981653d1f5661ed4e7c730eaea9
was: 'chg: remove SSI_BLOCK_CHLD and SSI_UNBLOCK_CHLD'

The changes in the other two files affected by this commit have already been
ported to spielwiese.
chg: port commit e9da36a from master to spielwiese

commit hash in master: e9da36afd8cdf7d84cd5f977ba1d25e86584165b
was: 'chg: in slCleanUp(), kill the link before freeing the memory'
chg: port commit 129ed66 from master to spielwiese

commit hash in master: 129ed66a74c2b5b0201c02efbc76fa49062d2fd2
was: 'rmv: remove attribute __attribute__((noreturn)) from m2_end()'
chg: port commit f860657 from master to spielwiese

commit hash in master: f860657053f1c0d3cdf380bc47fbd8fe81f49577
was: 'chg: remove special SIGCHLD handling for HPUX_9'

The file Singular/mpsr_sl.cc, which was also affected by this commit, has
been deleted anyway, see d828d63.
rmv: remove parallel_l.tst and realclassify_l.tst

These files are almost identical to parallel_s.tst and realclassify_s.tst,
but they are not used for the tests. Already removed in master.
fix: memory leaks
fix: memory leak
deleted unnecessary stuff using NTL in non-word size case
deleted more unnecessary stuff using NTL in non-word size case in univariate factorization
Merge pull request #365 from steenpass/changes_from_master

Changes from master (links, signals)
Merge pull request #366 from mmklee/memory_sw

Memory sw
fix memory leak while constructing rings
Reset default flags for omalloc

NOTE: SING_CHECK_SET_ARGS() leads to broken libomalloc :(
fix: memory leaks in factorization
Merge pull request #367 from mmklee/memory_sw

fix: memory leaks in factorization
chg: remove pselect
fix: auto-set --cpus depending on machine
(cherry picked from commit a105120f52f4e741b4e7ce0e3c6054111859f429)

Signed-off-by: Andreas Steenpass <steenpass@mathematik.uni-kl.de>
chg: re-enable system("cpu"), change setting of semaphore 0
(cherry picked from commit 71871dcf30b201439f1a4885b5dd9f6ecd140938)

Signed-off-by: Andreas Steenpass <steenpass@mathematik.uni-kl.de>
fix: close in m2_end
(cherry picked from commit 3189a3707ba12fa2348a78276959d7cfd9155040)

Signed-off-by: Andreas Steenpass <steenpass@mathematik.uni-kl.de>

Conflicts:
	Singular/misc_ip.cc (trivial)
fix: race between sig_term)hdl and m2_end in closing links
(cherry picked from commit 8435d8916aad63d28f131509cd17cb1e915dc8f4)

Signed-off-by: Andreas Steenpass <steenpass@mathematik.uni-kl.de>

Conflicts:
	Singular/silink.h
	Singular/ssiLink.cc
    (files moved, but these changes have already been ported anyway)
fix: m2_end
(cherry picked from commit b42514daaae54b8e43c3334010886a29dc3c90d1)

Signed-off-by: Andreas Steenpass <steenpass@mathematik.uni-kl.de>