CIG FAQ: update of the building cleaning schedule for 2017

The cleaning and waste disposal page of the CIG FAQ was updated with new information related to the cleaning:

https://www.unil.ch/cig/home/menuguid/faq/cleaning-and-waste-disposal.html 

Updated document: http://unil.ch/cig/files/live/sites/cig/files/FAQ/nettoyage/Planning_nettoyage_CIG_2017.pdf