New release : V0.8.0

New feature:
docbook + graphics (Plantuml)
process markdown as an input file

Bugfix:
BUG#031 : FOUserAgent: Image not found.
ERROR FOUserAgent: Image not found. URI: <path to="" file="">.png. (No context info available)</path>

Dependencies:
Use docbook xsl v1.78.1 => v1.79.1
Use fop v1.1 => v2.0 (and xmlgraphics v2.0.1)