Issue #105, allow user set of SSLContext options.

This commit allows full user control over the
contents of SSLContext options.  See:

examples/ssl_ctxoptions.rb

for two usage examples.

As usual, if this feature is not used, the gem behaves
as it has in the past.
Allow user set of parm for SSLContext.new(parm).

When using a hash connect, this commit effectively allows
the user to specifically request a particular SSL
method, e.g.:

:sslctx_newparm => :SSLv2, # ...

When using this feature it is the gem user's
responsibility to ensure that:

a) The Ruby version in use supports the requested
method, and
b) The broker used supports and allows the requested
method
Correct syntax error.