Fixes to community updates and welcome emails
Language updates
Make it possible to hide Sharetribe logo completely or leave only the S icon.
Enable community slogan and description texts in multiple languages.
fix spec tests
remember invitation code even if logging in with Facebook
Changes to invitation email
Language updates
Fix default terms (en & fi) to work also with white label communities
Language updates on error pages
few more cucumbers on green now
User can now log in also with his additional email

https://www.pivotaltracker.com/story/show/43126203
Fixed fb share text & tribe intro link color with dark custom colors.
Update fb meta information.
Started member email functionality.
Community admins can now send emails to members.
Remove usage of default_url_options in PersonMailer
Fixes to mail links
Simplify Invitations route
Minor change to community mailer