Remove trailing whitespace from most CMake and C/C++ code

Our Git commit hooks disallow modification or addition of lines with
trailing whitespace.  Wipe out all remnants of trailing whitespace
everywhere except third-party code.

Run the following shell code:

git ls-files -z -- \
 bootstrap doxygen.config '*.readme' \
 '*.c' '*.cmake' '*.cpp' '*.cxx' \
 '*.el' '*.f' '*.f90' '*.h' '*.in' '*.in.l' '*.java' \
 '*.mm' '*.pike' '*.py' '*.txt' '*.vim' |
egrep -z -v '^(Utilities/cm|Source/(kwsys|CursesDialog/form)/)' |
egrep -z -v '^(Modules/CPack\..*\.in)' |
xargs -0 sed -i 's/ \+$//'

Source/cmGlobalVisualStudio8Generator.h

@@ -24,9 +24,9 @@ class cmGlobalVisualStudio8Generator : public cmGlobalVisualStudio71Generator
 {
 public:
   cmGlobalVisualStudio8Generator();
-  static cmGlobalGenerator* New() { 
+  static cmGlobalGenerator* New() {
     return new cmGlobalVisualStudio8Generator; }
-  
+
   ///! Get the name for the generator.
   virtual const char* GetName() const {
     return cmGlobalVisualStudio8Generator::GetActualName();}
@@ -36,7 +36,7 @@ public:
 
   /** Get the documentation entry for this generator.  */
   virtual void GetDocumentation(cmDocumentationEntry& entry) const;
-  
+
   ///! Create a local generator appropriate to this Global Generator
   virtual cmLocalGenerator *CreateLocalGenerator();