adds pretender gem #34
adds dropdown list of users #34
adds dropdown list of users #34
adds impersonate routes #34
changes routes to get #34
adds named post routes #34

also has test code for showing impersonated user
routes, controller and form for pretender work #34
moves login links to nav bar #34

removes turbo links, removes paragraph from auth_links partial
adds link to add book #34
Layout cleanup #34

Move impersonate links to sidebar and use partial; Move logged in as
user to sidebar and use partial
specs and admin status helper #34

comment out redundant tests; add helper to display admin status;
Merge branch 'master' of https://github.com/ilynne/bookopotamus