Create user session management button

References: Issue #99
activities
add psych gem
Merge pull request #127 from codeforamerica/psych_fix

add psych gem
add eventbrites for a bunch of cities #codeacross
add Grand Rapids, MI to #codeacross
add South Bend to #codeacross
fix SF URL
update Norfolk #codeacross
add Philadelphia to #codeacross, add Code for Seattle forum, add Open Data Field Guide
denote fellowship cities for #codeacross
add space
try hr
format cities list
format cities table more
...
Fix the whitespace / failing spec
style locations table & add Honolulu to #codeacross
replace map
sort brigades