[Bug-gsl] Need input on inconsistency in gsl_ieee_env_setup docs

[Rhys Ulerich]

This line from the gsl_ieee_env_setup() documentation
(http://www.gnu.org/software/gsl/manual/html_node/Setting-up-your-IEEE-environment.html)
makes no sense

> If the requested modes are not supported by the platform
> being used then the function calls the error handler and
> returns an error code of GSL_EUNSUP.

as the relevant function signature is

> void gsl_ieee_env_setup (void)

The GSL_EUNSUP value is returned from gsl_ieee_set_mode within
gsl_ieee_env_setup's implementation, but the value is ignored and not
returned to the caller.

So:

a) Fix the documentation.  Easy.

b) Fix the API signature and implementation.  Presumably everyone's
ignoring the currently void return value anyhow and changing the
signature to return an int would harm no one.

Thoughts?

- Rhys