Fix missing max interval in xAxisConfigs
Fix missing max interval in xAxisConfigs

Missing max was causing graphs over 1yr with few very points (say,
monthly data) to default to a 12hrly xAxisConfig. Fixes #155

Krylon360/evernote-graphite-web,Talkdesk/graphite-web,Krylon360/evernote-graphite-web,evernote/graphite-web,Krylon360/evernote-graphite-web,evernote/graphite-web,Talkdesk/graphite-web,evernote/graphite-web,evernote/graphite-web,Krylon360/evernote-graphite-web,Talkdesk/graphite-web,Krylon360/evernote-graphite-web,Krylon360/evernote-graphite-web,evernote/graphite-web,Talkdesk/graphite-web,Talkdesk/graphite-web,Talkdesk/graphite-web