Merge pull request #48 from moztw/master

Update Thunderbird's system requirement page
Merge pull request #52 from moztw/master

Update the production site
Merge pull request #54 from moztw/master

Add GATC for translate and irclog sites.
Merge pull request #55 from moztw/master

Modify AB Test code
Firefox 20.0 release notes.
Firefox 20.0 release, news and download links.
Merge branch 'firefox-release'
Update Fx 20 notes, add one security fix note.
Merge branch 'master' into production
Add TB 17.0.5
Add TB 17.0.5
Fix URL typo
Add news, update link
Fix TB 17.0.5 release date
Merge branch 'master' into production

Conflicts:
	htdocs/thunderbird/releases/17.0.5/index.shtml
	htdocs/thunderbird/releases/index.shtml
first commit of /firefox/tw page

the first version of /firefox/tw
To-do:
1.style it with sandstone
2.take some screenshot of fx-tw-ver
3.make it more contents
Merge pull request #57 from mingtsay/firefox-tw

first commit of /firefox/tw page
Add keyword to description, re-structure the events.
Merge pull request #59 from moztw/master

re-structure events for contribute-2
Firefox 20.0.1 download link.