OOoLilyPond-0.5.9

Changes to OOoLilyPond 0.5.9 since 0.5.8 (May 2019):

* OLy will now automatically search for include files in the folder where the current LibreOffice document is located.
In case there are files with the same name in different folders, OLy will first look in the current LO document's folder.
Thus, include files from here will have priority over those from other folders that are specified in the include statement.

Thanks to Hannes E. Schäuble for this useful enhancement!