Disable can_set_mount_point in horizon local_settings

kvm doesn't support specifiying the mount point when adding a volume
so disabling this in the dashboard reduces confusion

Change-Id: Ibdb318a9382825ed0b868c4bf287dd8d2dab0d33
Updating man page and authors

Updated man page with output from packstack -o (we really need to
automate this in package building)
Added Most active Authors to to config.py (they appear in the man page)

Change-Id: I6c478143a05ce257cc1443a7c1a40a176bbf797c
Merge "Disable can_set_mount_point in horizon local_settings"