Log unexpected writes to the paths designated as part of a non-default mount

When populating a composite mount there are certain components that write content to it. Some of them are declarative and make it easy to infer the output, e.g. content package installer and Sling's repoinit.

Others are unpredictable, such as OSGi components/activators.

It would be useful to report such "unexpected" writes so that they can be analysed and disabled. The analyser would get the mount information from the MountInfoProvider and report:

• when such writes occur
• a stack trace of the write operation