* 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
* Certificate fingerprint length functions return an "int", so use an
int when calculating the length
* Clean up the OpenSSL certificate fingerprint if() and indentation mess
These operate on the SubjectPublicKeyInfo of the certificate, which does
change unless the private key is changed. This allows the fingerprint to
stay constant even if the certificate is reissued.
(The same fingerprint is also used by DANE)
