GenericSSLSocketFactory configurations documented in ssl_channels.adoc

[mchhil-incomm]

https://github.com/jpos/jPOS/blob/main/doc/src/asciidoc/ch05/ssl_channels.adoc

Should additional configuration that the socket factory can have be documented?

https://github.com/jpos/jPOS/blob/main/jpos/src/main/java/org/jpos/iso/GenericSSLSocketFactory.java#L350-L360