Declare variables, make it proper C++.

tutorials/fit/fitCircle.C

tutorials/geom/RadioNuclides.C

tutorials/geom/csgdemo.C

tutorials/geom/xtruSamples.C

tutorials/graphics/gaxis3.C

tutorials/graphics/manyaxis.C

tutorials/hist/DynamicSlice.C

tutorials/hist/hksimple.C

tutorials/hist/xyplot.C

tutorials/spectrum/DeconvolutionRL_wide.C

tutorials/spectrum/DeconvolutionRL_wide_boost.C