Allow the input tree or table to this item to be set to NULL.

This will be useful when we remove the input data in Visomics after
this item has been instantiated.

Change-Id: Id8d3f31d3249418365311181c9e4f1ee243ca6b5
fix compile error on Visual Studio 2008

This commit resolves the follow problems:
http://open.cdash.org/viewBuildError.php?buildid=2724142

Change-Id: I1c93bc0b40ed7bf5c3b6ed4a73ffacd4877b7023
fix some unused variable warnings

Change-Id: I52c678342d5e1c63c0e2fe4648dd1b902d5531c5
fix memory leaks in TestRInterface

Change-Id: I430b4123d5d66076ae1d01e628ebe771f158e248
Merge topic 'cleanup_RAdapter' into master

d168b6b2 fix memory leaks in TestRInterface
06b5cf19 fix some unused variable warnings
74d24249 fix compile error on Visual Studio 2008
Merge topic 'TreeHeatMap_RemoveInput' into master

cc1d5acd Allow the input tree or table to this item to be set to NULL.