This allows us to get rid of the hideous MATRIX_PATH_PART_EQUALS macro,
and prevents inconsistent usage of strcmp() (for example, !strcmp() vs
strcmp() == 0).
StrEquals() also has sensible behavior for dealing with NULL strings (it
doesn't just segfault like strcmp()).
This is useful for having a TLS and a non-TLS version port, like Synapse.
I verified that the multiple-servers does in fact work as intended,
although the TLS server part is broken; I must be doing something
incorrectly with LibreSSL in setting up the server.
This is the easiest and cleanest way to get logging into some of the
fundamental APIs, such as the database and TLS APIs. We don't want to
have to pass logging functions to those, but they can safely use the
global logging configuration.
This commit should fix user interactive authentication for dummy flows,
but I still have to implement a few more flows, including passwords and
refresh token. I also have to fix the cleanup logic: when do we purge
UIA sessions?
