Set modified date before processing image.

Allows image to save properly with non-nullable modified date column.
Merge pull request #84 from gauthierm/image-upload-modified-date

Set modified date before processing image.
prepare for release of 2.1.14
prepare for release of 2.1.15 | package party
Fix the definition of the id field in the SiteImageSetWrapper
Fix syntax error with the account login relocate

Introduced in https://github.com/silverorange/site/pull/83
Merge pull request #85 from isaacgrant/fix-image-set-wrapper

Fix the definition of the id field in the SiteImageSetWrapper
Merge pull request #86 from isaacgrant/session-page-fix

Fix syntax error with the account login relocate