Change ebib-call-file-viewer to open the first file name arg if the file path exists. The second n arg becomes optional for using a space-separated list of filenames. Previously, this function would choke on filenames containing spaces, since it would treat the space as a separator between multiple files. This works around that.
A single file path with spaces respects the relative search paths from ebib-file-search-dirs.
Switch file path selection order in ebib-call-file-viewer.
Merge branch 'fix-open-external-files-with-spaces' of git://github.com/lamberta/ebib into files-with-spaces
Allow spaces in filenames in the file field.

Thanks to Billy Lamberta for the idea and code contributions.