Bump version for development
Fix #49 subset.neuronlist's handling of NA in logical subsets

* these should be dropped as base::subset does
STY: code formatting in subset.neuronlist
Add soma argument to plot3d.neuron

* when TRUE plots a sphere at the neuron's StartPoint
* can also be numeric to specify radius
* fixes #47
* used in examples
boundingbox.im3d should return NULL when BoundingBox is undefined

* fixes #45
NEWS for last 3 fixes
give remotesync.neuronlistfh an indices argument

* closes #46
add a nice example of selective update with remotesync
fix: export ndigest.dotprops method

* and test this by adding an example that uses it
Add ndigest.neuron method

* closes #43
make image.im3d useRaster when possible

* but see https://github.com/jefferis/nat/issues/39 for discussion of why
  this doesn't work as it should
image.im3d will use plot images as rasters where possible

* noted 20x speed for medium size images
* closes #39 by modifying a few lines of image.default rather than deferring to
  image.default's (currently broken) logic for determining if rasterImage can
  be used.
Bump version to 1.4.4