FIX: tests now catch bug reported in #750 (in HDF5 output layer)
FIX: both data and label now copied correctly in HDF5 output layer
FIX: updating HDF5 input test for new test data
make "all" the default target

"all" is the right default since it builds the library itself.
define "everything" after it.
Merge pull request #813 from sergeyk/dev

Fix for bug in HDF5 Output Layer
Add NetState message with phase, level, stage; NetStateRule message with
filtering rules for Layers.
Incorporate NetState{,Rule} into Solver/Net.  Net::FilterParam
includes/excludes layers based on whether the NetState meets each
layer's NetStateRule(s).
Add INPUT layer so deploy nets can be incorporated as well.
Use unified train/test nets in examples.