After startup, and once per day, check the validity dates on our ssl certs,
and broadcast callbacks with the information so interested plugins can
know.
If our clock is < May 2016, we don't try to judge the certs, because clearly
we don't know what time it is.
- introduce lib/tls/mbedtls lib/tls/openssl
- move wrapper into lib/tls/mbedtls/wrapper
- introduce private helpers to hide backend
This patch doesn't replace or remove the wrapper, it moves it
to lib/tls/mbedtls/wrapper.
But it should be now that the ONLY functions directly consuming
wrapper apis are isolated in
- lib/tls/mbedtls/client.c (180 lines)
- lib/tls/mbedtls/server.c (317 lines)
- lib/tls/mbedtls/ssl.c (325 lines)
In particular there are no uses of openssl or mbedtls-related
constants outside of ./lib/tls any more.
