Various reviewer/editor type changes to the user guide.  The changes include
correcting some spelling and grammar mistakes.  Other changes include standardizing
on a single form of a word. Examples include i.e., BPMN, LDAP, JUnit, JSON, and JavaScript.
I either selected the common industry usage or the most prevalent usage in the
document.  Thus 'i.e.' was selected over 'ie.'.  In other cases where the usage was
large and split almost evenly I left them alone.  Such an example is 'eg.' vs. 'e.g.'.
Merge branch 'UserGuideChanges' of https://github.com/dbmalkovsky/Activiti
Small changes to userguide