feat(portal): add our own 404 template
feat(portal): add a nicer error (500) page
fix(common): use modular scale to define font sizes
fix(*): impose a standard for page headings and content sections
fix(common): reorganize base .styl spacing and typography

This implements standard font sizes, alignment and spacings across all pages.
Closes #86
feat(common): add styles for blockquotes
fix(projects): adjust Project.relevant_fact @ Project Details
fix(projects): fix Project .tags font-size
fix(feedback): clean up Feedback Create template
fix(common): fix form labels font weight
fix(accounts): clean Edit* page titles
Merge pull request #98 from brasilcomvc/fix/outline-styles

Fix: outline styles
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