Need a OWS version negotiation function...

[sdlime]

It would be helpful to eventually have some sort of a function to apply the
negotiation rules set forth in the various OGC specs. I believe the logic is
consistent from spec to spec. Input would be the requested version and an array
of supported versions and the result would be the version to return. Something like:

  int MS_NUMWCSVERSIONS = 2
  char *wcsVersions[MS_NUMWCSVERSIONS] = {"1.0.0", "1.1.0"};

  version = msOWSGetVersion(request->version, wcsVersions);

A requested version of 1.2.0 would return 1.0.0 and so on. Not a big deal for
WFS and WCS at the momement since there's only one version out, but for WMS I
would think version negotiation would be getting cumbersome. I see Julien has
already added functions to turn version strings into numbers so comparison is
easy so we're part way there.

Steve

BTW I've attached this to WMS component in lieu of a OWS component...