Add .travis.yml to .Rbuildignore
Add smat and smat_alpha
Set smat_alpha as default score matrix
Change nblast2 to nblast and fix getOption()
Merge branch 'master' of https://github.com/jefferislab/nat.nblast

* 'master' of https://github.com/jefferislab/nat.nblast:
  Update README.md
  re-roxygenise some doc changes
  export WeightedNNBasedLinesetMatching generic
  export nblast2.dotprops method
  Remove nat dependency (probably only for the time being)
  Missing private functions from PotentialSynapses and NeuriteMatchingFunctions
  Fix use of options in nblast defn and docs
  import nn2 function
  Switch RANN from depends to imports
  ignore .travis.yml
  Add Travis build shield to README

Conflicts:
	.Rbuildignore
	NAMESPACE
	R/neuriteblast.r