Merge branch 'issue/heat_example' into 'master'

corrected init file of heat example to support output

See merge request !75

examples/init/heat.dat.2d

-heatMesh->macro file name:    ./macro/macro.stand.2d
-heatMesh->global refinements: 4
+heatMesh->global refinements: 2
 heatMesh->min corner: 0 0
 heatMesh->max corner: 2 2
-heatMesh->num cells: 2 2
+heatMesh->num cells: 8 8
 
 heat->mesh:  heatMesh
 heat->names: u
@@ -13,10 +12,10 @@ heat->solver->break if tolerance not reached: 1
 heat->solver->info: 1
 heat->solver->left precon:    diag
 
-heat->output->filename: heat.2d
-heat->output->output directory: output
-heat->output->ParaView format: 1
-heat->output->ParaView mode: 1
+heat->output[0]->filename: heat.2d
+heat->output[0]->output directory: output
+heat->output[0]->ParaView mode: 1
+heat->output[0]->ParaView animation: 1
 
 adapt->timestep:    0.1
 adapt->start time:  0.0