RopenSci Kara Woo review

[x] Fix all noted errors/unexpected output in examples
[x] Don't force stringAsFactor on user session
[x] consistent messages across all functions: include message when no results as in NEH
[x] don't show HTTP message unless a new verbose argument is set to TRUE
[x] Fix gates documentation and allow full dates in search
[x] Better error message for invalid arguments/organizations.

ropensci / awardFindR