fixing bug #4760 documents import verif size limit
fixing bug #4760 documents import verif size limit
bug #4760 :  Generalize in one single point the generation of the error message for file size limit exceed. Fix the maximum file size computation in Mo

Conflicts:
	kmelia/kmelia-war/src/main/java/com/stratelia/webactiv/kmelia/control/KmeliaSessionController.java