STYLE: add documentation for FILE(REMOVE ...) and FILE(REMOVE_RECURSE ...)

FILE(REMOVE ...) works only for files, not for directories, REMOVE_RECURSE
works for both, it seems having both is not necessary

Alex

Source/cmFileCommand.h

@@ -77,9 +77,9 @@ public:
       "  FILE(GLOB variable [RELATIVE path] [globbing expressions]...)\n"
       "  FILE(GLOB_RECURSE variable [RELATIVE path] \n"
       "       [globbing expressions]...)\n"
-      "  FILE(REMOVE [directory]...)\n"
-      "  FILE(REMOVE_RECURSE [directory]...)\n"
-      "  FILE(MAKE_DIRECTORY [directory]...)\n"
+      "  FILE(REMOVE [file1 ...])\n"
+      "  FILE(REMOVE_RECURSE [file1 ...])\n"
+      "  FILE(MAKE_DIRECTORY [directory1 directory2 ...])\n"
       "  FILE(RELATIVE_PATH variable directory file)\n"
       "  FILE(TO_CMAKE_PATH path result)\n"
       "  FILE(TO_NATIVE_PATH path result)\n"
@@ -130,7 +130,11 @@ public:
       "match the files.\n"
       "Examples of recursive globbing include:\n"
       "   /dir/*.py  - match all python files in /dir and subdirectories\n"
-      "MAKE_DIRECTORY will create a directory at the specified location\n"
+      "MAKE_DIRECTORY will create the given directories, also if their parent "
+      "directories don't exist yet\n"
+      "REMOVE will remove the given files, also in subdirectories\n"
+      "REMOVE_RECURSE will remove the given files and directories, also "
+      "non-empty directories\n"
       "RELATIVE_PATH will determine relative path from directory to the given"
       " file.\n"
       "TO_CMAKE_PATH will convert path into a cmake style path with unix /. "