Allow to set modification date programatically.
Allow to set modification date programatically.

Re: #2400
johnpuddephatt/symphony-2,DavidForster/symphony-2,DavidForster/symphony-2,roshinebagha/Symphony-Test,jensscherbl/symphony,BloodBrother/symphony-2,bauhouse/sym-todo-list,alexnantel88/symphony-2,johnpuddephatt/symphony-2,brendo/symphony-2,mazedigital/jcilearn,ljonka/symphony-2,ljonka/symphony-2,symphonycms/symphony-2,symphonycms/symphony-2,roshinebagha/Symphony-Test,DeuxHuitHuit/symphony-2,jensscherbl/symphony,mazedigital/jcilearn,bauhouse/sym-todo-list,BloodBrother/symphony-2,twiro/symphony-2,avanteweb/symphony-2,jurajkapsz/symphony-2,twiro/symphony-2,michael-e/symphony-2,NikoMostWanted/symphony-2,michael-e/symphony-2,brendo/symphony-2,mazedigital/jcilearn,alexnantel88/symphony-2,jonmifsud/symphony-2,DeuxHuitHuit/symphony-2,jurajkapsz/symphony-2,avanteweb/symphony-2,NikoMostWanted/symphony-2,blaXXabla/projet_test_symphony,blaXXabla/projet_test_symphony,jonmifsud/symphony-2