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/cmGlobalVisualStudio6Generator.h

@@ -25,9 +25,9 @@ class cmGlobalVisualStudio6Generator : public cmGlobalVisualStudioGenerator
 {
 public:
   cmGlobalVisualStudio6Generator();
-  static cmGlobalGenerator* New() { 
+  static cmGlobalGenerator* New() {
     return new cmGlobalVisualStudio6Generator; }
-  
+
   ///! Get the name for the generator.
   virtual const char* GetName() const {
     return cmGlobalVisualStudio6Generator::GetActualName();}
@@ -35,15 +35,15 @@ 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();
 
   /**
    * Try to determine system infomation such as shared library
-   * extension, pthreads, byte order etc.  
+   * extension, pthreads, byte order etc.
    */
-  virtual void EnableLanguage(std::vector<std::string>const& languages, 
+  virtual void EnableLanguage(std::vector<std::string>const& languages,
                               cmMakefile *, bool optional);
 
   /**
@@ -52,8 +52,8 @@ public:
    */
   virtual std::string GenerateBuildCommand(const char* makeProgram,
                                            const char *projectName,
-                                           const char* additionalOptions, 
-                                           const char *targetName, 
+                                           const char* additionalOptions,
+                                           const char *targetName,
                                            const char* config,
                                            bool ignoreErrors,
                                            bool fast);
@@ -61,7 +61,7 @@ public:
   /**
    * Generate the all required files for building this project/tree. This
    * basically creates a series of LocalGenerators for each directory and
-   * requests that they Generate.  
+   * requests that they Generate.
    */
   virtual void Generate();
 
@@ -90,9 +90,9 @@ private:
   void GenerateConfigurations(cmMakefile* mf);
   void WriteDSWFile(std::ostream& fout);
   void WriteDSWHeader(std::ostream& fout);
-  void WriteProject(std::ostream& fout, 
+  void WriteProject(std::ostream& fout,
                     const char* name, const char* path, cmTarget &t);
-  void WriteExternalProject(std::ostream& fout, 
+  void WriteExternalProject(std::ostream& fout,
                             const char* name, const char* path,
                             const std::set<cmStdString>& dependencies);
   void WriteDSWFooter(std::ostream& fout);