User visible changes in `PRIMA.jl`

Version 0.1.1

Keywords for other constraints than bounds have been renamed as nonlinear_ineq for non-linear inequality constraints, linear_ineq for linear inequality constraints, and linear_eq for linear equality constraints.
In cobyla, if the caller is not interested in the values of c(x) expressing the non-linear inequality constraints, the number of such constraints may be provided instead of the array to store c(x).

First public version.