When XCA started in 2002, there were no C++ initializers.
Drop explicit initializers from the constructors.
- Fix indentations of section declarators.
- Replace NULL by nullptr when feasible.
- Sort private section: properties first, then methods.
If we have a QByteArray (ba) and must provide it to
a BIO* expecting OpenSSL function, the following
construct provides it: BioByteArray(ba).ro()
directly providing the QByteArray buffer as BIO
It also supports mixed writes:
BIO_write(bba, buf, size)
bba += QByteArray
