[Building Sakai] Peer review backport for 2.9.x

[Daniel Merino]

Dear community,

I have spent some time backporting the cool Longhsight's Peer Review 
Feature for 2.9.x, as we plan to use it in our 2.9.2 the next academic year.

I think that others have been interested too about this feature in the past.

FYI I have documented my work in 
https://confluence.sakaiproject.org/display/SPANISH/Peer+Review+Feature+-+Backporting+to+2.9.x

Don't worry, is in Spanish Confluence site but I have written it in english.

I hope that it will be useful for others that remain in 2.9 the next 
year. And of course, if somebody finds any issue or error do not 
hesitate to let me know.

Best regards.
-- 
Daniel Merino Echeverría
daniel.merino at unavarra.es
Gestor de E-learning - Centro Superior de Innovación Educativa.
Tfno: 948-168489 - Universidad Pública de Navarra.