OPM/opm-core — pull request #481 by atgeirr (2014-01-30 10:40:22+00:00)
Title: Fix summary output, now contains output for all steps.

Previously, the summary output was rewritten for each step,
leaving only the last step's data in the summary data file.

There are still some issues that should be thought about for summary output, such as:
- what units should be used in the output,
- what fields should we output.