Adss race list view
Adds list races template
Adds disable race function
Modifies disable form in order to accept races
modifies ballot model adding active and disable_reason fields
Adds id in ballot info
Adds disable view and urls needed
Merge remote-tracking branch 'origin/master-stage3' into dev2-stage3
Allows to enable races
Adds get_ballot function in sub_constituency model
Checks if race is enabled in barcode form
Checks if races is enabled in center details form
Removes missing prints
Merge remote-tracking branch 'origin/master-stage3' into dev2-stage3