Release 1.2.00 with FastStump optimizations

Corrected faststump bug : wrong subsequent call for getFilteredReverseBeginEnd(), invalidating "normal" iterators.Workaround provided : new function getFilteredandReverseBeginEnd(), returning pair of pair of iterators, normal and reverse.

FastStump Bug : first column was ignored (j = 1)
Minor change in OutputInfo::setOutputList(). If the output code is already present, it doesn't replace it.
The output history handles "fast resume"
outputIsActivated() added to OutputInfo.
The documentation of getOutputHistory.
getOutputHistory function added to OutputInfo. It allows to access the different metrics output directly.
The internal structure of OutputInfo changed from Vector to Map.
Minor change:  - Debug instruction removed. (found out after the push, so no possible amend)
Minor bug fix:  - Float comparison relaxed to epsilon-difference in the ConstantLearner selection.  - OutputInfo is not instanciated if --outputinfo is not provided.
Changes in CMakeLists.txt :- explicitly put the subdirectories of src dir
- put the Bzip2 sources in a separate (static) lib, in order to stop them to pollute builds and source file listings

Small cozmetics, enforce verbose = 0 for BaseLearner::createGenericStrongLearner and for all parsers
Corrected small bug, so TreeLearner learns a single node (stump) when numBaseLearners is set to 1. It used to build a tree of two nodes instead.
correct iterators for faststumps
preliminary fast stump
deleted cmake obsolete files