Warehouse base class added
refs #3692
Switching Indicators and Markers to new warehouse

Switch MaterialWarehouse over to Warehouse

Moving constraints over to Warehouse

Covert Dirac Kernel Warehouse over

Coverting VariableWarehouse over

Coverting PostprocessorWarehouse over

Coverting UserObject Warehouse over

Convert AuxKernel Warehouse over

Covert VectorPostprocessors over

Moving splits over

Coverting OutputWarehouse over

Convert Multiapp Warehouse over

Moving DGKernel Warehouse over

Moving Transfer Warehouse over

Moving Action Warehouse over

Moving BC Warehouse over

Move Dampers over
Adding an ImageFunction test which reads into an elemental variable
instead of a nodal variable.

The elemental variable field looks a lot more like the original image
when you have 1 pixel/element.

[original](https://drive.google.com/file/d/0B9BK7pg8se_iU2xFS19aUVVPOGs/edit?usp=sharing)
[elemental](https://drive.google.com/file/d/0B9BK7pg8se_iOUNSUlpfM1RNZUE/edit?usp=sharing)
[nodal](https://drive.google.com/file/d/0B9BK7pg8se_ieEw2S25VUU15S2M/edit?usp=sharing)

Refs #3544.
Merge pull request #3975 from permcody/warehouse_base_squash

Warehouse base squash
Update .gitignore to ignore new output file in phase_field module
Merge pull request #3978 from jwpeterson/image_function_test

Adding an ImageFunction test which reads into an elemental variable
Misc. enhancements to NodalFloodCount.{C,h}

* Use MooseSharedPointers for the file handles.
* Avoid multiple lg(N) lookups of the file handle.
* User can now select whether the NodalFloodCount threshold check is a
  less-than or greater-than check. By default, it is less-than.
* Delete commented-out line.
* Add/clarify comments.
* Delete unnecessary curly braces.
* Rename variable.
The NodalFloodCount object now computes the sum of grain volumes for
grains which intersect the boundary.

* Get the list of all boundary node ids in NodalFloodCount.C
* Detect intersection with boundary
* Store whether or not a bubble intersects the boundary in the
  BubbleData object.
* Add up all bubble volumes which intersect the boundary.
* Sum up the boundary intersecting grain volumes in parallel.
Remove old comment.
Make the _total_volume_intersecting_boundary array a class variable.
Scale boundary intersecting volume before printing.
Output the boundary-intersecting volume to the CSV file.
Delete boundary-intersecting volume print statement.
Ignore output file in new 'solution rasterizer' test.
Adding test computing boundary-intersecting volumes.

Eventually squash all input file/test updates into this commit.

* Use the new use_less_than_threshold_comparison
* Add CSV filename
  Current order of data is:
  timestep, time, volume-of-bubble-1, volume-of-bubble-2, ...
* Use new ImageMesh type
* It appears we do need execute_on='TIMESTEP' for the
  NodalFloodCountAux to show something.
* Add ProcessorIDAux.
* Add some results for different cells/pixel numbers.