This attempts to bootstrap network tests for MicroPython. This commits
sets test/net_inet/ as place for tests which require access to wide
Internet. They aren't intended to be run as part of the main testsuite,
instead to be run manually on demand.
test_tls_sites.py in particular check that it's possible to establish
SSL/TLS connection to select sites on the Internet: few references ones,
plus those for which problems were reported, and resolved.
Paul Sokolovsky