Bug 68660: pagefromfile handles not existing file

Handling of not existing file added.
Filename existence is checked, user can input a new filename in case or
quit.

Help is shown if user quits or should IOError still occurs.

Change-Id: Ide672e331c9084c74641be7b4633ace7216ef31b
Merge "Bug 68660: pagefromfile handles not existing file"