Add variable definition file for French

Add variable definition file plugins/org.dita.pdf2/cfg/common/vars/fr-fr.xml for
French.

Signed-off-by: Olivier Carrère <carrereo@gmail.com>
Acked-by: Angela Cristina <acristina@redaction-technique.org>
README: add procedure to build PDF

- Get and install latest DITA-OT full easy install version
- Get DITA XML branch of project
- Copy variable definition file for French in DITA-OT directory
- Build current content version from ditamap

Signed-off-by: Olivier Carrère <carrereo@gmail.com>
Acked-by: Angela Cristina <acristina@redaction-technique.org>
Script to remove extra blank lines: add support for .dita files

Edit script to support .dita files.

Signed-off-by: Olivier Carrère <carrereo@gmail.com>
Acked-by: Angela Cristina <acristina@redaction-technique.org>