Add more details to WFS html listing

[pnuu]

There are more details available that could be added for available datasets (StoredQuerys) to WFS info listing. Few that I've noticed with a quick glance are:

• calibration coefficients
• calibration function (e.g. y = ax + b)
• calibrated units (e.g. mm)

[pnuu]

Also list all properties (e.g. wind speed, wind direction, ...) that can be queried by setting the params keyword argument. This might be available via the link in the <om:observedProperty> tag.