The problem was that some PerfData labels contained several whitespace characters,
not just one, and therefore it was parsed incorrectly in `SplitPerfdata()`. I.e. the condition
in line 144 checks whether the first and last character is a normal quote, but since the
label can contain spaces at the beginning and at the end respectively, this caused the problems.
This PR fixes the problem by removing all occurring whitespace from the beginning and end,
before starting to parse the actual label.
This allows for a faster config load due to less locking required.
The change is slightly backwards-incompatible. Before, you could manipulate the
globals namespace at a later stage, but disallowing this feels reasonable for
the performance benefit alone (which especially shows on many-core machines).
Apart from that, it's doubtful if doing so is even useful at all as the DSL
provides no mechanism for you to synchronize your operations that may run in
parallel. The data structures itself are protected from race conditions, but
anything implemented on top of this may still be subject to race conditions.
And even if some user has a good reason for doing this, there's a feasible
workaround by creating your own namespace like globals.mutable and using that
instead.
If a connection hangs for too long in ApiListener#NewClientHandler(),
ApiListener#AddConnection()'s Timeout calls boost::asio::basic_socket#cancel()
on that connection to trigger an exception which unwinds
ApiListener#NewClientHandler(). Previously that unwind could trigger a Defer
which called boost::asio::ssl::stream#async_shutdown() which extended the hang.
Normally if for some reason an ack comment still exists on a checkable not
acked anymore, still clean it up. But while replaying log config objects
incl. ack comments come before check results and acks. I.e. 1) ack comment,
2) DOWN check result and 3) ack. Not 1) DOWN check result, 2) ack and 3) ack
comment. So the checkable is temporarily not acked, but already has the ack
comment. In this case the DOWN check result which is older than the ack
comment shall not clean up the latter.
