hide safeslinger for now

safeslinger talk is not final confirmed.
李慕約abstract修正

id呼叫成kirby的，已經修正
議程表文字預設靠左
Merge branch 'develop'
Merge branch 'develop'
Merge branch 'master' into develop
Merge branch 'develop' of https://github.com/g0v/summit.g0v.tw into develop