add yourtalentagents.com

they are likely going to want to change their URL before the conference
Merge pull request #18 from colindean/sponsor/yta

add yourtalentagents.com
Removes sponsorship opportunities info
Updates index to reflect end of sponsorship deadline
Removes another sponsorship thing
updated gittip logo
Merge pull request #19 from colindean/sponsor/gittip

updated gittip logo
Adds Intridea and Squaremouth sponsorships
Replaces brynary's talk with Julie's talk
Adds image of Julie
Add Julie's abstract and bio
Merge pull request #20 from juliepagano/master

Add Julie's abstract and bio
Removes expired hotel block information
Update YTA web site URL
add description for YTA
Add YTA description
Updated YTA description from sponsor