Update nat citation with Zenodo DOI
Add basic implementation of pointsinside based on Rvcg

* Rvcg::vcgClost has a signed distance function but the result
  only seems to make sense for whole brain surfaces
* but not neuropil surfaces
* assume this has to do with how they are closed
Update to match up with fixed surface normals
Add test for pointsinside
minor doc fix - prune.dotprops has moved to nat
Merge branch 'feature/points-in-surf'

* feature/points-in-surf:
  minor doc fix - prune.dotprops has moved to nat
  Add test for pointsinside
  Update to match up with fixed surface normals
  Add basic implementation of pointsinside based on Rvcg
Verbatim version of nat.as::InterpolateAlongNeuron
basic implementation of resample.neuron

* dependent functions
Always recalculate seglengths
Add test for resample.neuron
Add two more tests that reveal bugs in resample.neuron
Fix bug in resample.neuron
Consistent return values for as.seglist.neuron

* always returns list of lists when all=TRUE
  even when there is only one subtree
update resample docs inc FIXME resample.neuron

* resample.neuron doesn’t handle width or multiple subtrees
give seglengths a flatten option (true by default)

* i.e. can return list of seglengths vectors for each
  subtree
Merge branch 'feature/resample-neuron'

* feature/resample-neuron:
  update resample docs inc FIXME resample.neuron
  Fix bug in resample.neuron
  Add two more tests that reveal bugs in resample.neuron
  Add test for resample.neuron
  Always recalculate seglengths
  basic implementation of resample.neuron
  Verbatim version of nat.as::InterpolateAlongNeuron
seglengths can return length of each edge in segment
additional examples for seglengths
dotprops.neuron now provides the option to resample

* closes #129
suppress remote tests if flybrain can’t be reached

* nb introduces httr in suggests