Add sub2ind() + test
Add coord2ind() + test
Add ind2coord() + test
Fix roxygen and other errors picked up by R CMD check
Add dotprops.{im3d, character} methods + test
Add dotprops attribute wrt source file setting and update test to match
Remove SetFileInfo argument from dotprops.character()
Fix mirror so that vectors for dotprops are recalculated

Also ensure that attributes of transformed object are carried across.
Merge branch 'dotprops.im3d' of github.com:ajdm/nat into ajdm-dotprops.im3d

* 'dotprops.im3d' of github.com:ajdm/nat:
  Remove SetFileInfo argument from dotprops.character()
  Add dotprops attribute wrt source file setting and update test to match
  Add dotprops.{im3d, character} methods + test
  Fix roxygen and other errors picked up by R CMD check
  Add ind2coord() + test
  Add coord2ind() + test
  Add sub2ind() + test
Merge branch 'ajdm-dotprops.im3d'

* ajdm-dotprops.im3d:
  Remove SetFileInfo argument from dotprops.character()
  Add dotprops attribute wrt source file setting and update test to match
  Add dotprops.{im3d, character} methods + test
  Fix roxygen and other errors picked up by R CMD check
  Add ind2coord() + test
  Add coord2ind() + test
  Add sub2ind() + test
don't set mostattributes after mirroring

* this should be handled elsewhere if necessary
* the only place where attributes will get lost at the moment is in 
  xform.dotprops because that recalculates the dotprops
Copy attributes when constructing a dotprops object from an existing one

* this means that xform of a dotprops passed an exact equality round trip test
  in the same way that would be true for a neuron
* or more exactly a neuronlist containing dotprops (since otherwise 
  as.equal.dotprops looks after things)
* still not sure that this behaviour is exactly what is wanted
Merge branch 'ajdm-fix/mirror'

* ajdm-fix/mirror:
  Copy attributes when constructing a dotprops object from an existing one
  don't set mostattributes after mirroring
  Fix mirror so that vectors for dotprops are recalculated

Conflicts:
	R/dotprops.R (adjacent edits in dotprops character and dotprops methods)