Fixed attachment download issue.

Passing in the array, as opposed to the ArraySegment would cause some
attachments to download incorrectly.  It would add extra bytes into the
attachment (dependent on the size of the remaining bytes of the last
buffered segment as compared to the buffer size)
Merge branch 'master' of https://github.com/couchbaselabs/couchbase-lite-net into development
(On iOS at least) it would throw a cast exception as "possible_anscestors" is a JArray.  Add an extension method to use in these cases similar to how dictionaries are handled.
Fixed casting issues.
Normalized tabs. Remove async/wait cruft from test.
Normalized tabs.
Merge branch 'jonlipsky-sync_issues'