Correct minor spelling and grammar errors in help doc.

This change makes some slight corrections to some errors that I noticed
when I was going through the Vdebug help documentation.
Revert some changes from commit 2c62f9c3.

I made some changes to the help doc with regards to pull request #108
that are incorrect.  This commit reverts those changes.
Merge pull request #108 from dkinzer/master

Correct minor spelling and grammar errors in help doc.