changed mail delivery settings, from address to Thoughtsy
viewing message no longer sends extra email; reposted thoughts expire to reposted state; update testing
additional testing
updated message tests
add columns to queue, add 'answered_at' to posts
replaced 'unanswered' and 'available' scopes with 'queued' and 'answerable'
add sort_date for better sorting Post index, queue, and available post queue