Add strip whitespace and check on write

Change-Id: I73ac4260a379c208b1574a934fdbdfb191e5f152

.vimrc

@@ -16,6 +16,7 @@ if filereadable(expand(vundle_dir) . "/README.md")
     Plugin 'tpope/vim-fugitive'
     Plugin 'tpope/vim-surround'
     Plugin 'ctrlpvim/ctrlp.vim'
+    Plugin 'rhysd/vim-clang-format'
     " Plugin 'shougo/neocomplete'
     Plugin 'godlygeek/tabular'
 
@@ -26,6 +27,8 @@ else
     command CloneVundle execute "!git clone " . vundle_repo . " " . vundle_dir
 endif
 
+highlight Search ctermbg=5
+
 filetype plugin indent on    " required
 syntax on
 
@@ -36,6 +39,25 @@ set expandtab " On pressing tab, insert 4 spaces
 set mouse=a
 set hlsearch
 
+" Warn for trailing whitespace. Search with wrap (w) do not move cursor (n)
+function! WhitespaceWarn()
+    echohl WarningMsg
+    echo 'Found whitespace.'
+    echohl None
+    echon ' Type :TrailWhitespace to remove it'
+endfunction
+function! StripTrailingWhitespace()
+    " Save cursor position
+    let l:save = winsaveview()
+    " Remove trailing whitespace
+    %s/\s\+$//e
+    " Move cursor to original position
+    call winrestview(l:save)
+    echo "Stripped trailing whitespace"
+endfunction
+autocmd BufWritePost * if search('\s\+$', 'wn') | call WhitespaceWarn() | endif
+command TrailWhitespace call StripTrailingWhitespace()
+
 " Hybrid line numbers on active buffer
 set nu rnu
 augroup numbertoggle