NCBC-552: Ensure that bucket throws ObjectDisposedException

When a thread calls Dispose on a bucket and no other thread is referencing
it, subsequent operations will fail with an ObjectDisposedException: "This
bucket [{0}] has been disposed! Performing operations on a disposed bucket
is not supported!"

Change-Id: Ib3c8d96a48a9e24c102133c8f37b37792acb150d
NCBC-556: SslConnection uses obsolete GetBuffer method - throws NIE

Change-Id: I44fa6e43c9b606f83789c6258c75f6a0c623d98d
NCBC-553: Could not bootstrap bucket with ssl connection

Fixes configuration bug that caused the bucket configuration settings to
be ignored. This in turn would make the client fail when attempting to
bootstrap because the urls and ports used would be non-ssl. Additional
unit tests and a property (IsSecure) were added to make it easier to
determine if the connection is indeed secure.
Change-Id: Icb174a516cf3e529154d5b51ccd23bcf1f77cc57