(in prior action, Texas Supreme Court held that land ownership includes an interest in groundwater in place, and that limiting a private owner’s water usage for a public purpose constitutes a taking requiring the payment of just compensation under the Texas Constitution; ultimately, however, Court remanded case for determination of whether denial of permit in amount of water requested by landowners constituted taking after full development of record; on remand, court held that regulatory taking occurred when water was limited to amount inadequate for landowners’ pecan orchards and just compensation was amount by which property impaired by taking).