CVS commit by lunakl: 

Move all code responsible for showing/hiding windows, setting mapping
state, NET::Hidden etc. to one function: Client::updateVisibility().


  M +38 -39    client.cpp   1.453
  M +2 -2      client.h   1.179
  M +45 -1     manage.cpp   2.73
  M +3 -3      workspace.cpp   1.506