Refactor User#update_last_seen! and User#update_tracked_topics
some topic-list simplification
catching up with the master

Merge remote-tracking branch 'upstream/master'
further simplification over all, changes include: flatter button style, styling admin table, topic-list style
fixes wrong placement of expect in header integration test
fixes wrong placement of expect in View Topic integration test
merging with the new category nav feature

Merge remote-tracking branch 'upstream/master'
category nav style
require `X-Frame-Options: SAMEORIGIN` for clickjack prevention
Merge pull request #1582 from awesomerobot/master

continuing default theme simplification/fixes
Declare rack-protection dependency explicitely
making post-info text brighter, making category nav dropdown text smaller and bold
Merge pull request #1586 from awesomerobot/master

making post-info text brighter, refining category nav dropdown
Version bump to v0.9.7.2
Merge pull request #1585 from raul/prevent-clickjacking

Require `X-Frame-Options: SAMEORIGIN` for clickjack prevention
Merge pull request #1584 from velesin/view_topic_test_fix

fixes wrong placement of expect in View Topic integration test
Merge pull request #1583 from velesin/header_test_fix

fixes wrong placement of expect in header integration test
Merge pull request #1571 from novemberkilo/master

Refactor User#update_last_seen! and User#update_tracked_topics
A better script for bumping the version
integration tests for the logo part of header