Fix bug where PDF does not display in IE 8-10
Add PDF support detection and handling for IE
Implement a 10-second timeout
Eliminate the need to hide and show the document

Converted loading message into a modal overlay, and hide it when
document is loaded. This also fixes a bug in IE8 where showing a
previously hidden iframe with PDF crashes the browser.
Add fancy fade out effect on document load
Fix IE10 bug where the document could remain stuck
Log conversion info and errors using Rails.logger
Simplify routes
Change "source" query string parameter to "url"
Update functional test to reflect change in param