Add Length unit & update code

This commit follows the same strategy as the Time unit
and contains hand-written versions (copy-n-paste style)
of the various Time implementations. Any bugs that exist
in them will also exist here.

Code changes are also in place for supporting physicalSize
fields based on `Length`, but several FIXMEs are in place
for changes that need to take place one the Bio-Formats
submodule has been bumped.
Corrections from Mark
Add 2 UnitsFactory implementations

Like the ColorFactory classes, one in rendering and one in blitz,
the UnitsFactory implementations should be the central location
for creating unit objects and converting back and forth between
either the ome.model or the omero.model representations and those
in ome.xml.
Include generated ome-xml source in Eclipse
Convert all Length fields in ome and omero models

This should bring the OMERO classes up-to-date with regard
to the Bio-Formats length unit changes. Modifications stop
in the pojo data objects by marking methods as @Deprecated
which need to have a unit added to their signature.  Those
methods which specified in their javadoc that a given unit
was to be used are not marked as deprecated. The factories
in the rendering/ and blitz/ components should contain all
helpers for converting and making units.
5.1DEV__13: add schema files sans upgrade
Merge 'origin/develop' into units-length

Conflicts:
	components/blitz/src/ome/formats/model/ChannelProcessor.java
Fix blitz ant build
Fix insight compile error
Units: Add Temperature support
Units: Add Pressure support
Code changes for temperature and pressure
Minor fixes to variable names
Units: Add Frequency support
Units: Add ElectricPotential support
Units: Add Power support
Reinstate column quoting for 'power'
Fix typo in name of ElectricePotential.ice
Fix cpp_obj_reg includes
More small but critical fixes