Replace substitute() with string slicing
Simplify system() string with quotes and redirection
Use echoerr instead of manual highlighting
Improve initialization

 - Move version check out of the autoloaded file
 - Check for dependencies at the beginning instead of with each
   invocation
Add SprungeBuffer that posts the current buffer
Clean a little by using a script-local variable
Merge pull request #1 from Osse/master

Merge Osse enhancements and additions