Update tools
Simplify implementation of default tools
Add TODO to comments where necessary
Once again change how default values work
Use --dev in examples/test
Don't specify defaults for min_border* properties
Rename Props.scala to HasFields.scala
Make toSerializable return Option[Any]
Apply default value semantics changes to DataSpecs
Don't set default value for size/radius in Glyph/Circle
Rename Units -> SpatialUnits and AngleUnits -> AngularUnits
Rename DataType to ValueType
Add Vectorized, Spatial and Angular replacing DataSpec
Fix defaults for spatial and angular units
Use screen units for length field
Use degrees for pressure_angle field
Add ValueType type member to Enum
Add glyphs/Gears example
Update bokehjs
Vectorized must serialize at least {"value": null}