An OCaml library for manipulating papiers repositories
The /papiers/ binary now uses Papierslib
Some more documentation for papierslib
Implement a new field: language

Conflicts:
	lib/formatInfos.ml
	lib/inner_db.ml
	lib/inner_db.mli
	src/archive.ml
	src/commands.ml
	src/metadata.mli
  & other modifs
Minor style improvement
Do not crash when trying to get metadata from invalid PDFs

Conflicts:
	lib/formatInfos.ml
Add an -exact/-e option to search & lucky, to require exact matching

Conflicts:
	lib/query.ml
	lib/query.mli
	src/commands.ml
add a "help" command; "papiers help foo" is equivalent to "papiers foo --help"
Merge branch 'master' into papiers-lib