Version 3.0, pre-release 2

This is the first pre-release of das2py build against das2C version 3. It supports das2 and das3 streams. The included das_verify script provides stream validation for both versions.

One major API change from the 2.X series is present. The function read_http now returns two values. As follows:

dHdr, lDs = das2.read_http('some_url')

where dHdr is the stream header along with any defined coordinate frames, and lDs is the list of datasets, as before.

For a description of new features in das3 streams, see the related das2C pre-release notes.