Handle ASLR when invoking test functions
Don't crash if no tests are found at runtime
Be more verbose in testnode_t::dump()
Implement get_file_descriptors() for Darwin.
Removed unused variable from Darwin intercept code.
Minor cleanups in Darwin intercept code.
Use the correct attribute for NP_PARAMETER

to avoid clang optimising it out entirely.
Avoid %p in NP_ASSERT_NOT_NULL

because the actual string produced is system dependent, and this breaks
the tnannullfail test which expected to see "(nil)" as seen on Linux and
on Darwin instead got "0x0".
Use fprintf not syslog in tnna test

because syslog is broken right now and this test doesn't need to use it.
Minor cleanups in the Linux intercept code.
Use the correct addresses when adding auto mocks

...yet more ASLR fallout.