Last minute changes...

By writing output byte by byte, the calling parallel make would start
jobs depending on the completed files too soon.

Avoid this by writing to temporary files and move the completed results
into place.

Fixes: #1921

Output a proper error message instead of a more cryptic assert
if the vmod writer does the wrong thing.

Ref: #1811

Pointed out by Jean-François Laurens.

Conflicts:
	bin/varnishd/cache/cache_fetch.c

whitespace) testfiles.

Spotted by:	Coverity

In particular, this avoids a later backend.list attempt on a file descriptor
to a dead process and, consequently, avoids a long delay in varnishtest
when varnishd cant be started (for instance, because it is not in PATH).

Ref: #1924

Related to #1924.

Fixes #1924.

This reverts commit 47a1ef06.

Not needed after 7dec1221.

As discussed with phk: Callers of Lck_CondWait with timeout should
be prepared for early wakeups.

Reduces my stash list to 62 entries.

Conflicts:
	doc/sphinx/dev-guide/index.rst

This was already called and has not been any changes since then.

a family of tickets related to it (#1933 #1920 #1898 (?) #1888 and #1865 (?))

We may not have permission to unlink vp.dir

$ /etc/init.d/varnish_master restart
Stopping Varnish Cache:                                    [FAILED]
Starting Varnish Cache: Assert error in mgt_VccCompile(), mgt/mgt_vcc.c line 302:
  Condition((rmdir(vp.dir)) == 0) not true.
  errno = 13 (Permission denied)

eat all CPU time.