feat(accounts): add User picture field
feat(accounts): add the User's picture field to Edit Personal Info
fix(accounts): change User.picture file format to JPEG

This will reduce final file size without compromising the image quality.
feat(accounts): define specs for User.picture sizes
feat(accounts): add default styles for displaying User.picture
feat(accounts): display User.picture_medium at Edit Dashboard
feat(accounts): add User.picture_small to the header
feat(accounts): add a widget to output User.picture easier
feat(accounts): display a default image when User has no picture
feat(common): define styles for User.picture @ header @ smartphones
feat(common): add custom front-end for image fields
fix(accounts): use ID instead of email onto User.picture filename
Merge pull request #87 from brasilcomvc/feat/user-picture

Feature: user picture