BlockRestrictable isn't broken
BlockRestrictable isn't broken

It turns out that the initialization routine calls other routines in the class but
only _after_ it has populated variables needed by those other members. If the
_initialized variable is set earlier, there's no problems raised by the new
assertions.

closes #7088

permcody/moose,laagesen/moose,friedmud/moose,friedmud/moose,idaholab/moose,laagesen/moose,andrsd/moose,lindsayad/moose,milljm/moose,SudiptaBiswas/moose,yipenggao/moose,jessecarterMOOSE/moose,bwspenc/moose,dschwen/moose,dschwen/moose,harterj/moose,katyhuff/moose,backmari/moose,backmari/moose,Chuban/moose,permcody/moose,dschwen/moose,idaholab/moose,SudiptaBiswas/moose,liuwenf/moose,stimpsonsg/moose,liuwenf/moose,milljm/moose,jessecarterMOOSE/moose,nuclear-wizard/moose,SudiptaBiswas/moose,sapitts/moose,YaqiWang/moose,andrsd/moose,jhbradley/moose,liuwenf/moose,YaqiWang/moose,idaholab/moose,sapitts/moose,lindsayad/moose,yipenggao/moose,sapitts/moose,bwspenc/moose,backmari/moose,andrsd/moose,katyhuff/moose,lindsayad/moose,katyhuff/moose,jhbradley/moose,andrsd/moose,SudiptaBiswas/moose,idaholab/moose,bwspenc/moose,jhbradley/moose,dschwen/moose,yipenggao/moose,sapitts/moose,friedmud/moose,joshua-cogliati-inl/moose,stimpsonsg/moose,idaholab/moose,joshua-cogliati-inl/moose,liuwenf/moose,jessecarterMOOSE/moose,andrsd/moose,bwspenc/moose,liuwenf/moose,harterj/moose,backmari/moose,jessecarterMOOSE/moose,Chuban/moose,nuclear-wizard/moose,YaqiWang/moose,jessecarterMOOSE/moose,milljm/moose,dschwen/moose,jhbradley/moose,laagesen/moose,bwspenc/moose,joshua-cogliati-inl/moose,sapitts/moose,Chuban/moose,milljm/moose,nuclear-wizard/moose,harterj/moose,joshua-cogliati-inl/moose,permcody/moose,milljm/moose,YaqiWang/moose,SudiptaBiswas/moose,friedmud/moose,nuclear-wizard/moose,permcody/moose,liuwenf/moose,lindsayad/moose,Chuban/moose,harterj/moose,laagesen/moose,katyhuff/moose,harterj/moose,stimpsonsg/moose,lindsayad/moose,yipenggao/moose,laagesen/moose,stimpsonsg/moose