Fixed typos, prettified output

 - Fixed some mis-spellings
 - Changed output text for consistency
 - if no args are given, do not print command undefined not found

I also reformatted to code for consistency.

I tested this on my systems but please test this patch before accepting it.

I also sent a pull request to nodeamir: (The error was just for testing purposes. The bug in that pull request is not in this patch.)
https://github.com/arunoda/nodemiral/pull/9

If they accept it, mup should look a lot nicer!