[CB-3527] Update Upgrading Guide for 2.7.0 -> 2.8.0 for iOS
[CB-2332] Document FileTransferError.body
Added 2.8.0 upgrade step
[CB-3555] [BlackBerry10] Update getting started guide

- target type now specified using -t
- run now calls build rather than the reverse
added version 2.8.0rc1
[CB-3559] adding 2.6.0 upgrade guide for blackberry