[mac] small tweak on download-repo-dialog
Merge pull request #162 from Chilledheart/temp

[mac] small tweak on download-repo-dialog
only display activities tab when supported
[mac] tweak the spacings of download-repo-dialog
Merge pull request #163 from Chilledheart/temp

[mac] tweak the spacings of download-repo-dialog
do not show rotate icon when repo in "sync init" state
added @2x icons
added more 2x icons