typos in package docs
Example to emphasise registration dir search order
fix docs for bridging_sequence

* closes https://github.com/jefferislab/nat.templatebrains/issues/7
Merge branch 'master' of github.com:jefferislab/nat.templatebrains

# By James Manton
# Via James Manton
* 'master' of github.com:jefferislab/nat.templatebrains:
  Minor documentation improvements

Conflicts:
	R/transformation.R (docs for bridging_sequence, kept GJ)
	man/bridging_sequence.Rd (regenerated)