Version 2.30

CHG: For :FilePlus, :WritePlus, :SavePlus, when a [count] but no [!] is given, try to create an offset one more than an existing file between the current and the passed offset. This lets you use a large [N] to write the file with the next number within [N] for which no file exists yet. Change inspired by
http://stackoverflow.com/questions/13778322/vimscript-code-to-create-a-new-numbered-file
Version 2.31

- Minor: Also handle :echoerr errors, which don't have an E... number prepended.
- FIX: Non-any completion can yield duplicate roots, too (e.g. foobar.orig.txt + foobar.txt).
- Add dependency to ingo-library (vimscript #4433). *** You need to separately install ingo-library (vimscript #4433) version 1.014 (or higher)! ***