More precise packet length checking.

Issue discovered using valgrind and the Codenomicon TLS test suite.
Better check for null signature method.

Issue identified using valgrind and the Codenomicon TLS test suite.
initialize to null the SRP extension data on allocation.

Issue identified using valgrind and the Codenomicon TLS test suite.
doc update
Corrected an off-by-one error.

The issue was discovered using the codenomicon TLS suite.
When generating ECDSA keys, generate 256-bit keys by default.

Curves with less than 256 bits (i.e., SECP192R1 and SECP224R1) are
not widely supported.

Conflicts:
	src/certtool-common.c
doc update
bumped version
Do not use autogen's file option for input parameters.

Instead use a string. We check the file for validity and autogen's
check was imposing rules such as normal file (as opposed to a device),
that were not needed.