sample_laplace_log_incidence_poisson: Generate Laplace samples of incidence
In incidental: Implements Empirical Bayes Incidence Curves

This function generates Laplace samples of posterior distribution for a vector of reported incidence.

sample_laplace_log_incidence_poisson(
  beta_hat,
  beta_cov,
  reported,
  Q,
  num_samps_per_ar = 10
)

`beta_hat`	Maximum likelihood solution for beta parameter.
`beta_cov`	Covariance of objective solution (either Fisher information or Hessian inverse).
`reported`	An integer vector of reported cases.
`Q`	Spline basis matrix.
`num_samps_per_ar`	Number of Laplace samples to return for each AR path.