Removing trailing whitespace

It's better if you don't add new trailing whitespace at the end of lines. Use a text editor which allows you to easily spot/clean trailing whitespace or configure it to do so. For instance:
 * craigbarnes/nanorc for nano;
 * Komodo Edit: Edit > Preferences > Save Options > (check) Clean trailing whitespace and EOL markers > (check) Only clean changed lines;