Code contributors:

Rodolfo Ribeiro Gomes (rodolforg AT gmail.com)
	- An initial code for the constraints of type teacher(s) max span per day and teacher(s) min resting hours.
	- The alphabetic sorting of the items which respects the user's locale (the special characters are correctly ordered).

Marco Vassura
	- The colors of the timetables, in the timetable view dialogs and in the XHTML results (using CRC-24 based on RFC 2440 Section 6.1).
