warnings: fix narrowing warnings

When assigning to a C array, all of the types should be no "larger" than
the cast-target type. This is enforced in C++11, but has become a
warning otherwise in preparation for C++11 in many compilers.

Change-Id: I30f148c46387566c16d58229baeafc6b83dfb0f7
TestSurfacePlot: loop using vtkIdType

The 'inc' variable will take care of the implicit float cast. Avoid the
implicit downcast when passing i and j as indicies though.

Change-Id: Ia84dc4b67c102c0da3c0bd5ef43bd89d0e861e0d
vtkQuaternionInterpolator: call the constructor properly

The old code was calling operator() which returns the value at that
index. This is why initializer lists are better than assignment blocks,
but that's a larger discussion.

Change-Id: I01d20e14494786ce60553789f6027784851a68bc
warnings: remember values with the proper type

Storing these as integers truncates the actual value when restoring.

Change-Id: I5fd5eee053db12a1c96c51dd359cd9410d0f68a6
warnings: use static casts to point out precision loss

Lots of places where we pass floating point values as integers; make the
loss of precision more explicit.

Change-Id: Icafde395f0463421b5f36d1e4e855fa25cab5ab4
warnings: use floating point intermediate values

When calculating values which are, at the end, integers, the
intermediate values may have some nuance to them where floating point
can help precision.

Change-Id: I4b9cd14f80b74200ae4fde1369a51c5d4275cd18
warnings: resolve unused variables

Change-Id: I23752fa1c7f5f6b15f3737eb35c78231f023bfa3
vtkOpenGLImageMapper: fix unintentional shadowing

Change-Id: I7cc94d59f7f8ae8de7a6e9ddf7f308f00fa3ad89
warnings: fix signed/unsigned comparison warnings

Change-Id: Id129123f393d45b6858fb0db14dd110bd303252e
vtkOpenGLProperty: remove unused function

Seems to have been copy/paste from the old OpenGL module.

Change-Id: If0475c3507da715db9e9fb5425ce839916f9649e
Merge topic 'dashboard-warnings-20140728' into master

6e38c6b9 vtkOpenGLProperty: remove unused function
6bd7e617 warnings: fix signed/unsigned comparison warnings
72fd2024 vtkOpenGLImageMapper: fix unintentional shadowing
3ed64fc0 warnings: resolve unused variables
37aad40d warnings: use floating point intermediate values
76a3ce4a warnings: use static casts to point out precision loss
830ef1b8 warnings: remember values with the proper type
db92b37a vtkQuaternionInterpolator: call the constructor properly
fba50fba TestSurfacePlot: loop using vtkIdType
ede46c84 warnings: fix narrowing warnings