Allow multiple .bib files in \bibliography command

Allow multiple .bib files in \bibliography command

2007-10-20  Joost Kremers  <joostkremers@yahoo.com>

	* ebib.el (ebib-local-bibtex-filenames): renamed from
	ebib-local-bibtex-filname. this is now a list of strings, rather
	than a string. thanks to Sinisa Pajevic for pointing out that a
	\bibliography command can contain more than one .bib file.
	(ebib-extract-bibfiles): removed.
	(ebib-get-local-databases): modified to return a list of database
	filenames. also now uses insert-buffer-substring, rather than a
	combination of buffer-string and insert.
	(ebib-insert-bibtex-key): modified so that it can handle multiple
	bibtex files. this reflects the change to
	ebib-local-bibtex-filenames.
	(ebib-entry-summary): same.

The manual was updated to reflect the new functionality.