DONE refector config, especially look and display defaults look_limit look_index_header display_limit display_index_header sort_buffersize
DONE change so index_header is False by default in representations
DONE redo all docstring examples
DONE add subsection to changes in 1.0 about 'u' functions removed
DONE add subsection to changes in 1.0 about config
DONE make sure use field names rather than naked header
DONE integrate dbtests with other tests
DONE add documentation about contributing
DONE add running stats
DONE revise documentation about dependencies, add information about optional dependencies
DONE port petlx.array
DONE port petlx.dataframe
DONE port petlx.xls
DONE port petlx.xlsx
DONE port petlx.hdf5
DONE port petlx.sql
DONE merge sqlite3 module into db module
DONE port petlx.interval
DONE port petlx.index
DONE add documentation to changes section about ported xls, xlsx, array, dataframe, hdf5, sql, intervals, merged sqlite3 ...
DONE validate module: implementation, documentation
DONE look truncate
DONE display truncate
DONE review all issues