CySolver and cyrk_ode optional arguments and extra output must be float64s numbers

[jrenaud90]

For performance and simplicity reasons, it was decided that the optional arguments (args) passed to both the CySolver and cyrk_ode solvers must be given as floating point numbers (no complex values, strings, booleans, etc). It would be nice to offer the ability to pass other types of values via the args parameter.

For the same reasons, the optional capture of additional outputs for both solvers is also limited to certain types (floats for CySolver; floats or complex for cyrk_ode).

[jrenaud90]

Commit 67358c2 and tag v0.7.0 mistakenly cited this issue. It did not address this.