Limit number of concurrent session

[jgebal]

Currently number of sessions used by client= 1 + number of reporters.
This is 2 sessions at minimun and can esily grow to 5-6 sessions.

I suggest a change, where we use separate reporter session only for reporters that are givin output to the screeen.
In pracrive that would mean - we use only 2 sessions 99% of the time.

Currently i sometimes hit a limit of max open sessions per user in some databases when using utplsql-cli + IDE connection to the database.