Fixes issue #19 -- multiple daemons now ignore each other.

Each instance now writes a (hidden) file to its working directory, listing all filenames it may write to. Other instances collect all these files and ignore them.

Prepares solution of issue #7 as we now have a list of all files we don't want to copy.
Merge branch 'master' of https://github.com/akerbos/ltx2any

Conflicts:
	ltx2any.rb