Install editors helper files

Docs/CMakeLists.txt

@@ -1,2 +1,4 @@
 string(REGEX REPLACE "^/(.*)" "\\1" REL_CMAKE_DATA_DIR "${CMAKE_DATA_DIR}")
+install(FILES cmake-help.vim cmake-indent.vim cmake-syntax.vim DESTINATION ${REL_CMAKE_DATA_DIR}/editors/vim)
+install(FILES cmake-mode.el DESTINATION ${REL_CMAKE_DATA_DIR}/editors/emacs)
 ADD_SUBDIRECTORY (bash-completion)