This is a demo of particle swarm optimization with constraint support in Julia, and this demo is rewrited from tisimst/pyswarm.
pso(func, lb, ub; constraints=nothing, args=(), kwargs=Dict(), swarmsize=100,
omega=0.5, phip=0.5, phig=0.5, maxiter=100, minstep=1e-8, minfunc=1e-8,
verbose=false, particle_output=false)