File for charts parametrable
BUGFIX: definition and proof of prop.4

Proof of prop.5 is still bogus.
BUGFIX: prop that LUniv is better than LU

Both the proposition and the proof have been carefully corrected.
Add isUnvalent algorithm
Add a section for LUnivRPI
Begin LUnivRPI presentation
Some minor corrections
Begin experiments section
Add a bib entry
Merge remote-tracking branch 'portable/master'
Some small improvements
Very small english correction
Add bibliographic entries
Presentation of earlier works

I don't really like it yet.
Merge commit '1cd2021a5f0cd46aab28827c8f33058f7bcda0d8' into feature/paper

* commit '1cd2021a5f0cd46aab28827c8f33058f7bcda0d8':
  Presentation of earlier works
  Add bibliographic entries
  Very small english correction
  Some small improvements
  Add a bib entry
  Begin experiments section
  Some minor corrections
  Begin LUnivRPI presentation
  Add a section for LUnivRPI
  Add isUnvalent algorithm
  BUGFIX: prop that LUniv is better than LU
  BUGFIX: definition and proof of prop.4
  File for charts parametrable