title: How to detect modified files and save in eclipse?
body: <p>I have a plugin which work with special json config files,and it can be runned by the Run button.
  I make changes to the config without saving the file.
  If I the hit the run button to try it out, plugin will use the config as it is on disk...
  It would be nice if the tool would either save all files before running - 
  or at least give a warning message that tells me that some files are not saved..</p>
  
  <p>How can i detect modified files and get a list of this files?</p>
  
  <p>How can i save changes in this files?</p>