Custom profile fields

Giving the user the ability to specify profile fields and added
r_fullprofile.
added another test for r_fullprofile
Added 'profileFields' option

This is to allow the developer to request specific profile fields. NOTE:
if the profile fields option is passed along with the scope option, the
scope option is ignored.
add example
Merge branch 'master' of https://github.com/jschell12/passport-linkedin-oauth2 into jschell12-master
minor
1.1.0