This is a huge patch that should be a global NOP.
For unix type platforms it enables -Wconversion to issue warnings (-> error)
for all automatic casts that seem less than ideal but are normally concealed
by the toolchain.
This is things like passing an int to a size_t argument. Once enabled, I
went through all args on my default build (which build most things) and
tried to make the removed default cast explicit.
With that approach it neither change nor bloat the code, since it compiles
to whatever it was doing before, just with the casts made explicit... in a
few cases I changed some length args from int to size_t but largely left
the causes alone.
From now on, new code that is relying on less than ideal casting
will complain and nudge me to improve it by warnings.
Teach lws how to deal with date: and retry-after:
Add quick selftest into apt-test-lws_tokenize
Expand lws_retry_sul_schedule_retry_wsi() to check for retry_after and
increase the backoff if a larger one found.
Finally, change SS h1 protocol to handle 503 + retry-after: as a
failure, and apply any increased backoff from retry-after
automatically.
