naijR v0.6.3.9006

New Features:

• Introduced ngdist, a dist object containing road distances (in km) between all 37 Nigerian State capitals, sourced from UNDP.
• Added ng_distance() for convenient lookup of the driving distance between any two State capitals, with support for kilometers and miles.

Bug fixes:

• Fixed non-interactive vignette builds due to a failure to explicitly import key functions.