switched up svol example
removed utils
added random walk process for svol model
fixed trace size calculation for svol model
fixed up find_MAP to work better with various optimizers
added trigamma function and gradient to psi
added exponential
leads to errors if value is an array and the replacement value is a scalar
added framework for testing distributions
fixed tests
sign error
added ctontinuous dist tests and corrected errors
added summary plot for trace
history -> trace
ARM example errors
examples now found recursively
import plot
removed extraneous file
history -> trace everywhere
merged distributions branch