PR# 5556 Warn user when opening the same project in multiple EiffelStudio sessions

Unexpected behavior can occur if the same EiffelStudio project is opened in multiple sessions. This can occur across the network when the project folder is available on the network, or on a Windows server when a user can log in more than once (or multiple users can be logged in) and try to use he project simultaneously.

I'd like EiffelStudio to warn me when this is occuring, and ask if I really want to proceed. 

I'd prefer that EiffelStudio not prevent me from doing this, just warn me. Given the difficulty of providing bullet-proof exclusive access on Windows, and the potential for locking a project and making it unusable, I'd like to be able to bypass the warning and proceed with opening the project, if at all possible.

Just open the same project twice in different EiffelStudio sessions. Try running a debug session in one while changing code and recompiling in the other.