* Move certificate, key, DH parameters and configuration to heap
(Documentation states that setting new configuration, e.g.
during a rehash, is unsupported while connections using that
configuration are active)
This is the same approach as the fix for #186
Refcount these structures so as to not introduce a memory leak
On rehash, it will use new structures only if there are no
errors in constructing them
* Make fingerprint generation work for TLS connections
See the comments in the newly created file for an explanation
* Fix memory leak when generating a fingerprint from a file
* Add better error-reporting (strings in addition to numbers)
where possible
* Coalesce several connection memory allocations into one function
* Reduce boilerplate where possible (Charybdis targets C99)
* Support private key being in certificate file, and having no
DH parameters file
* Correct erroneous closing comment
