Ecl2df

Fixes:
* Bugfix for gruptree module, solving issues with multiples trees. Refactored, and incurs deprecation of one function.
* Revert deprecation for non-datetime indices in summary module introduced in last version. Added workarounds for supporting Eclipse summary files going beyond year 2262, which is tricky in Pandas.

Breaking changes:
* In fipreports, the column "WATER_TOTAL" has been renamed to "WIIP_TOTAL".

New features:
* ECL2CSV forward model now supports options supplied from ERT config file.
* Dataframe objects returned from summary.df() have metadata for each column vector attached in a dict in df.attrs["meta"].
* All command line tools can output to stdout by providing the magic filename "-".
* WSEGVALV keyword is supported in the compdat module.
* summary.df will give warning if datetime=True is not supplied. In the future, the returned dataframe will always have a datetime index. This does not affect CSV export.

Bugfixes:
* Fix PVTG include file export

Bugfix release: Avoid crash with WSEGSICD support from v0.8.3

New feature:
* Write synthetic UNSMRY files from CSV/dataframes.

Feature additions:
* WSEGAICD and WSEGSICD supported in compdat
* weekly frequency for summary extraction
* Gruptree root node included in dataframe output

Changes/bugfixes:
* Python 2 support dropped
* Bugfix zonemap file parsing
* Fix usage of logging, letting client scripts set the logging level.

Support defaulted I and J in COMPDAT when WELSPECS is present.