Extend SSL_CONF to return command value types.

Add certificate and key options.

Update documentation.

The function gettimeofday() is not supported on all platforms. Use
more portable versions. Adapted from FIPS code.

Removing RSA+MD5 from the default signature algorithm list
prevents its use by default.

If a broken implementation attempts to use RSA+MD5 anyway the sanity
checking of signature algorithms will cause a fatal alert.

Suggested by: Anton Blanchard

Latest MIPS ISA specification declared 'branch likely' instructions
obsolete. To makes code future-proof replace them with equivalent.

Excessive fragmentation put additional burden (of addtional MAC
calculations) on the other size and limiting fragments it to 1KB
limits the overhead to ~6%.

PR: 3139

Improve decrypt performance by 10-20% depending on platform. Thanks
to Jussi Kivilinna for providing valuable hint. Also thanks to Ard
Biesheuvel.

Submitted by: Yuriy Kaminskiy

PR: 3130

Suggested by: Ard Biesheuvel