Initial version of Lavision Imspector reader

Metadata population still needs work, as does support for larger stacks.

See ticket #8071.
ome-xml: Add joda-time 2.2 as a build dependency
ome-xml: Timestamp uses Joda Instant and DateTime internally for ISO-8601 dates

Internal timezone representation: UTC in milliseconds (Instant)
Input timezone representation: Defined in ISO-8601 string
Output timezone representation: UTC

The date handling is made reproducible and consistent by using UTC
everywhere.  If it's a non-UTC date on input, we convert to UTC.

The input and output of native Java Date and Calendar types is not
currently affected; we don't convert to UTC in input, but this is
an amendment which should be considered.
ome-xml: Timestamp: Remove unneeded imports
ant/toplevel.properties: Add joda-time-2.2.jar
ome-xml: Timestamp: Remove pointless DateTime usage in asSqlDate()
Update Imspector reader to support larger datasets
CellWorx: populate StartTime/EndTime on PlateAcquisition

These values are just taken from the AcquisitionDate on the first and
lates Images.

Conflicts:

	components/bio-formats/src/loci/formats/in/CellWorxReader.java
merge develop -D org -I include -E exclude: PR 528 (Tile performance improvements for VMS and NDPI)
merge develop -D org -I include -E exclude: PR 618 (Xml annotation)
merge develop -D org -I include -E exclude: PR 619 (xsd-fu: Improve Timestamp date handling and precision)
merge develop -D org -I include -E exclude: PR 620 (Add support for Lavision Imspector data)
merge develop -D org -I include -E exclude: PR 621 (CellWorx: populate StartTime/EndTime on PlateAcquisition (rebased onto develop))