AgeModel: Stochastic SRA to calculate the trajectory given parameters
In colemonnahan/sraplus:

Stochastic SRA to calculate the trajectory given parameters

1 2	AgeModel(Catch, AgeMat, Steep, NatMort, AgeMax, Carry, Weight, InitialDeplete, Sigma, AgeVulnOffset = -1, ProcessError = TRUE, simulation = NULL)

`Catch`	To do
`AgeMat`	Age at maturity
`Steep`	Steepness
`NatMort`	Natural mortality
`AgeMax`	Maximum age, above which there is a plus group.
`Carry`	Carrying capacity.
`Weight`	Vector of weights at age, calculated from growth parameters a and b.
`InitialDeplete`	Initial level of depletion.
`Sigma`	Process error variance, i.e. N(0,Sigma).
`AgeVulnOffset`	Optional parameter for specifying age at vulnerability, defaulting to AgeMat-1. See ?run.SIR for more info.
`ProcessError`	A flag for whether to include process error, defaults to TRUE.
`simulation`	A list with elements 'NYears' and 'FishMort'. If supplied the model will run a simulation under that level of U. It it designed to be used to test equilibrium conditions but can be expanded later for more expansive simulation testing.