Adds message when starting to disconnect computer monitor

* Adds message when starting to disconnect computer monitor with screwdriver.
* replacing \blue with span class stuff in messages.
Adds some messages during computer construction steps

* Adds messages for the player when wrenching, welding, putting cable and glass panel during computer construction steps.
* Also adds messages when the player doesn't have enough cable or glass.
'caution'->'notice'
Merge pull request #3288 from phil235/ComputerBuildFix

Adds some messages during computer construction steps