Fix issue with mutagen session management when multiple instances are in place

[glo47154]

The issue is about how a current session is looked for. If session names are like abc, abc-1, abc-2, then grep -i abc can give an incorrect result as all of those will pop out.

Possible solutions:

• to store session ID and not use grep for its name
• to fix grep e.g., check for the exact match in the whole line

[glo47154]

Development on the feature/multiple-instances-with-same-folder-name-error branch.

[glo47154]

Released in 3.0.2