Using http_texture_load as the test subject, library looks clean. Did
some better shutdown in the program itself and it looks better. Libcurl
itself is making a lot of noise. Adapted testrunner to run valgrind as
well but the memory allocation tester in the tools themselves grossly
interferes with Valgrind operations.
This brings in a copy of llmessage's llsdmessage testing server. We run
a mocked HTTP service to handle requests and the integration tests run
against it by picking up the LL_TEST_PORT environment variable when running.
Add some checks and output to produce useful info when run in the wrong
environment and when bad status is received. Later will add a dead port
as well so we can test that rather than use 'localhost:2'.