add userModified detection attribute to modified annotations

[BryonLewis]

resolves #1563

• Adds 'userModified' detection attribute that is set when a user modifies a track.
• When a track is modified, you will get a pencil icon next to it in the display and the detection attribute 'userModified' will be set to true.
• This will happen on all values, even 1.00 values from the detections
• Adds a UserCreated track attribute to all tracks that are created by a user.
• There is a Text option to turn on/off the pencil icon for indicating tracks created by a user, it is off by default.

[naglepuff]

A couple of linting suggestions and one question about some of the wording. Other than that this appears to work as intended

[naglepuff]

Should this message be "Show user edited icon?"

[BryonLewis]

It should be both created for created tracks and modified or edited for detections that have been modified.