FourierFlows/FourierFlows.jl: FourierFlows v0.1.1

Updates in BarotropicQG module: Adds ForcedParams in BarotropicQG module (in a similar manner as in TwoDTurb. Now BarotropicQG can be run in four different modes: (i) using Params runs 2D turbulence on a beta-plane (with or without topography). (ii) using ForcedParams and calcFq! function runs forced 2D turbulence on a beta-plane (with or without topography). (iii) using ForcedParams and calcFU function runs 2D turbulence on a beta-plane (with or without topography) that also includes a large-scale domain-averaged zonal flow U(t) which is forced by calcFU(t). (iv) using ForcedParams and both calcFq! and calcFU function runs forced 2D turbulence on a beta-plane (with or without topography) that also includes a large-scale domain-averaged zonal flow U(t) forced by calcFU(t). Optimizes the vars and calc_N! function to reduce memory allocation. Improves comments and simplifies the examples scripts in examples folder. Adds section "Basic usage" in documentation where all AbstractTypes are explained in detail