README: Remove mention of android support

Our android support is only a proof of concept so far.
test_that_matchtimeout...: Reduce test run-time

...from ~20s to <1s on my laptop. Setting `timeout_secs=0` guarantees
that at one frame will be processed (and then it will raise a
MatchTimeout if the frame didn't match). Setting `is-live=true` also
makes a big difference.