add a few macro helpers
require eigen3
add some useful multivariate sampling functions

uses eigen for some heavy lifting
add multivariate log-gamma function
add normal inverse wishart message type

also regen the protobuf files
add our NIW implementation
formatting
initial commit of the python NIW
NIW: rename mu0 -> mu and lambda -> kappa
WIP: NIW cython extension compiles now
NIW dbg: bug fixes
WIP: NIW dbg: various bug fixes
copy args on load()/dump()

returning refereces leads to unintuitive behavior
a few bug fixes to get tests passing
move wishart samplers into the random module

also add a simple test case for sample_inverse_wishart
add score_student_t comparison test
add NIW/NIX comparison test
note on score_student_t
add mattjj's code + license
add eigen3 dep to travis.yml