Document some core SSL_CTX and SSL methods.

Current thought is to organize this by:

- Core SSL_CTX APIs (creating, destroying)
- Core SSL APIs (creating destroying, maybe handshake, read, write as
  well)
- APIs to configure SSL_CTX/SSL, roughly grouped by feature. Probably
  options and modes are the first two sections. SSL_TXT_* constants can
  be part of documenting cipher suite configuration.
- APIs to query state from SSL_CTX/SSL, roughly grouped by feature. (Or
  perhaps these should be folded into the configuration sections?)

The functions themselves aren't reordered or reorganized to match the
eventual header order yet. Though I did do the s -> ssl rename on the
ones I've touched.

Also formally deprecate SSL_clear. It would be a core SSL API
except it's horrible.

Change-Id: Ia7e4fdcb7bad4e9ccdee8cf8c3136dc63aaaa772
Reviewed-on: https://boringssl-review.googlesource.com/4784
Reviewed-by: Adam Langley <agl@google.com>
2 files changed