imtcp: Document streamdriver.name.
imtcp: Document streamdriver.name.

Closes issue rsyslog/rsyslog-website#32.

sematext/rsyslog-doc,qha/rsyslog-doc,qha/rsyslog-doc,qha/rsyslog-doc,janmejay/rsyslog-doc,sematext/rsyslog-doc,sematext/rsyslog-doc,sematext/rsyslog-doc,qha/rsyslog-doc,janmejay/rsyslog-doc,janmejay/rsyslog-doc,janmejay/rsyslog-doc