BUG: Expose unusable functions

These functions were not covered in code coverage, and they
do not build.

Change-Id: Ie30712bc89ae0af79c05125178e363ad98bd5325
BUG: Incomplete refactoring of member variable name

The member variable name for this class is m_Offset.  These were
incorrectly coded, but went undiscovered due to lack of coverage,
and the fact that these functions are never used.

Change-Id: I7464d2b06d827288d44734c8b6af894d55ba69a5
STYLE: Allow system installed expat library with ITK_USE_SYSTEM_EXPAT=ON

Change-Id: I848f006063f27de4cdaf35e3a84de102caadb39f
BUG: Fix memory leak in LBFGSBOptimzierv4

Valgrind defect detected for the LBFGSBOptimizerv4:
http://open.cdash.org/viewDynamicAnalysis.php?buildid=3356652

Change-Id: I2cf4515d436c085c59a3f9ab54ca9a5f7e4a5f89
ENH: Uninitialized scalar field

Coverity defect:
Non-static class member is not initialized in this constructor nor in
any functions that it calls.

These were missed or new since the previous patch addressing this defect.

Change-Id: I369c7ed5ca9bece63ad30f4be4d9f00e1dd13fbd
Merge topic 'FixIncorrectMemberVariableNameAccess'

89e2a618 BUG: Incomplete refactoring of member variable name
5984b22d BUG: Expose unusable functions
ENH: Add distance vector to KdTree search API

In KddTree class, the distance vector is computed by the internal
"NearestNeighbors" class. However, this distance vector is not provided
as an API, instead in the examples the "EuclideanDistanceMetric" is used
to compute the distance vector.
This patch adds a new signature for the KdTree::Search function that
returns the distance vector as an argument.
Also a test unit is designed that shows that distances computed by the
metric are the same as the distances taken directly from the search
function.

Change-Id: I8130d73c1306caff2327b2ecd764dc84f2e95d12
Merge topic 'Coverity_UninitializedScalarField2'

51843eae ENH: Uninitialized scalar field
Merge topic 'lbfgsb_ml2'

3dd89bae BUG: Fix memory leak in LBFGSBOptimzierv4
Merge topic 'addDistanceVectorToKdTree_2'

45276d5c ENH: Add distance vector to KdTree search API
Merge topic 'ExternalExapt_ITK_USE_EXTERNAL_EXPAT'

ad260804 STYLE: Allow system installed expat library with ITK_USE_SYSTEM_EXPAT=ON