Improve conversion to data log in ephys formats

[MichaelClerx]

• ~ABF: Replace different methods with a single one with switches~
• Make sweep joining optional
• Use 0. etc naming for sweeps when not joined
• Use channel names in log
• Similar for ATF
• Similar for WCP

Full to-do in #985

[MichaelClerx]

Grepping for datalog vs data_log shows very little public API using either:

./myokit/tests/test_datablock.py:    def test_from_data_log(self):
./myokit/tests/test_formats_wcp.py:    def test_data_log_conversion(self):
[michael@localhost myokit]$ grep "datalog" ./myokit/ -Ir
./myokit/gui/datalog_viewer.py:#        'icon-datalog-viewer.ico',
./myokit/gui/datalog_viewer.py:#        'icon-datalog-viewer-16.xpm',
./myokit/gui/datalog_viewer.py:#        'icon-datalog-viewer-24.xpm',
./myokit/gui/datalog_viewer.py:#        'icon-datalog-viewer-32.xpm',
./myokit/gui/datalog_viewer.py:#        'icon-datalog-viewer-48.xpm',
./myokit/gui/datalog_viewer.py:#        'icon-datalog-viewer-64.xpm',
./myokit/gui/datalog_viewer.py:#        'icon-datalog-viewer-96.xpm',
./myokit/gui/datalog_viewer.py:#        'icon-datalog-viewer-128.xpm',
./myokit/gui/datalog_viewer.py:#        'icon-datalog-viewer-256.xpm',
./myokit/gui/datalog_viewer.py:            '.csv': self.load_datalog,
./myokit/gui/datalog_viewer.py:            '.zip': self.load_datalog,
./myokit/gui/datalog_viewer.py:    def load_datalog(self, filename):
./myokit/_bin/install-lin/myokit-datalog-viewer.desktop:#Icon=<?=icons?>/icon-datalog-viewer.png
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-1-empty.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-2-windows.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-3-old-mac.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-4-empty-lines.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-5-semicolons.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-6-open-string.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-7-empty-lines-2.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-8-unquoted-header.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-9-double-quoted-header.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-10-just-spaces.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-11-just-a-semicolon.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-12-bad-header.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-13-header-with-empty-1.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-14-header-with-empty-2.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-15-header-with-empty-3.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-16-wrong-columns-in-data.csv')
./myokit/tests/test_datalog.py:        path = os.path.join(DIR_IO, 'datalog-17-non-float-data.csv')
./myokit/tests/test_simulation_cvodes.py:        # Tested against offline method in test_datalog.py
./myokit/__init__.py:from ._datalog import (     # noqa
./myokit/__main__.py:    place_file(path, 'myokit-datalog-viewer.desktop', True)
./myokit/__main__.py:    import myokit.gui.datalog_viewer
./myokit/__main__.py:    myokit.gui.run(myokit.gui.datalog_viewer.DataLogViewer, *filenames)

Public:

• myokit.DataLog (two words)
• Module myokit.gui.datalog_viewer (one word)
• DataLogViewer (two words)
• Some filenames use datalog (one word)

[MichaelClerx]

Sometimes just called "log":

• DataBlock1d.from_log & to_log
• DataBlock2d.from_log & to_log
• myokit.prepare_log

[MichaelClerx]

Closed in #998