#10 PyDiskImage does not check for mounted file systems

[John Sullivan]

When the user choose to create, restore, or verify an image and selects a file system that is currently mounted, unexpected results may occur. For example, a file system that is mounted with read/write access will change between subsequent verifications, so the MD5 checksum verification will always fail.

PyDiskImage should perform a check before a create, restore, or verify operation, and if the file system chosen by the user is mounted, warn the user that the operation is likely to produce unexpected (and almost certainly undesirable) results.