Establish connection to all servers in workspace on extension activation

[isc-bsaviano]

This will address Chad's issue with many sessions being created at startup if manyeditor tabs are open. vscode-objectscript does this so you can follow that example.

[isc-klu]

I need help w/ duplicating Chad's issue. My workspace have 5 tabs/files open. The files are from two client-side folders and one server-side folder (the %SYS namespace). I reopen the workspace and expect 7 processes (one per file + one per each of the other two extensions) under my user name on Management Portal > System > Processes. I saw only one.