Xlrd-ignore-writeaccess-corruption

+ Decouple Book init & load.
+ runxlrd: minor fix for xfc.
+ More Excel 2.x work.
+ is_date_format() tweak.
+ Better detection of IronPython.
+ Better error message (including first 8 bytes of file) when file is
not in a supported format.
+ More BIFF2 formatting: ROW, COLWIDTH, and COLUMNDEFAULT records;
+ finished stage 1 of XF records.
+ More work on supporting BIFF2 (Excel 2.x) files.
+ Added support for Excel 2.x (BIFF2) files. Data only, no formatting
info. Alpha.
+ Wasn't coping with EXTERNSHEET record followed by CONTINUE
record(s).
+ Allow for BIFF2/3-style FORMAT record in BIFF4/8 file
+ Avoid crash when zero-length Unicode string missing options byte.
+ Warning message if sector sizes are extremely large.
+ Work around corrupt STYLE record
+ Added missing entry for blank cell type to ctype_text
+ Added "fonts" command to runxlrd script
+ Warning: style XF whose parent XF index != 0xFFF
+ Logfile arg wasn't being passed from open_workbook to
compdoc.CompDoc.

------------------------

- Added support for Python 3.7.
- Added optional support for defusedxml to help mitigate exploits.
- Automatically convert ``~`` in file paths to the current user's home
directory.
- Removed ``examples`` directory from the installed package. They are still
available in the source distribution.
- Fixed ``time.clock()`` deprecation warning.

----------------------

- Fix for parsing of merged cells containing a single cell reference in xlsx
files.

- Fix for "invalid literal for int() with base 10: 'true'" when reading some
xlsx files.

- Make xldate_as_datetime available to import direct from xlrd.

- Build universal wheels.

- Sphinx documentation.

- Document the problem with XML vulnerabilities in xlsx files and mitigation
measures.

- Fix :class:`NameError` on ``has_defaults is not defined``.

- Some whitespace and code style tweaks.

- Make example in README compatible with both Python 2 and 3.

- Add default value for cells containing errors that causeed parsing of some
xlsx files to fail.

- Add Python 3.6 to the list of supported Python versions, drop 3.3 and 2.6.

- Use generator expressions to avoid unnecessary lists in memory.

- Document unicode encoding used in Excel files from Excel 97 onwards.

- Report hyperlink errors in R1C1 syntax.

Thanks to the following for their contributions to this release:

- icerevalgmail.com
- Daniel Rech
- Ville Skyttä
- Yegor Yefremov
- Maxime Lorant
- Alexandr N Zamaraev
- Zhaorong Ma
- Jon Dufresne
- Chris McIntyre
- coltleesegmail.com
- Ivan Masá

-------------------

- Official support, such as it is, is now for 2.6, 2.7, 3.3+

- Fixes a bug in looking up non-lowercase sheet filenames by ensuring that the
sheet targets are transformed the same way as the component_names dict keys.

- Fixes a bug for ``ragged_rows=False`` when merged cells increases the number
of columns in the sheet. This requires all rows to be extended to ensure equal
row lengths that match the number of columns in the sheet.

- Fixes to enable reading of SAP-generated .xls files.

- support BIFF4 files with missing FORMAT records.

- support files with missing WINDOW2 record.

- Empty cells are now always unicode strings, they were a bytestring on
Python 2 and a unicode string on Python 3.

- Fix for ``<cell>`` ``inlineStr`` attribute without ``<si>`` child.

- Fix for a zoom of ``None`` causing problems on Python 3.

- Fix parsing of bad dimensions.

- Fix xlsx sheet to comments relationship.

Thanks to the following for their contributions to this release:

- Lars-Erik Hannelius
- Deshi Xiao
- Stratos Moro
- Volker Diels-Grabsch
- John McNamara
- Ville Skyttä
- Patrick Fuller
- Dragon Dave McKee
- Gunnlaugur Þór Briem

--------------------

- Automated tests are now run on Python 3.4

- Use ``ElementTree.iter()`` if available, instead of the deprecated
``getiterator()`` when parsing xlsx files.

- Fix 106 : Exception Value: unorderable types: Name() < Name()

- Create row generator expression with Sheet.get_rows()

- Fix for forward slash file separator and lowercase names within xlsx
internals.

Thanks to the following for their contributions to this release:

- Corey Farwell
- Jonathan Kamens
- Deepak N
- Brandon R. Stoner
- John McNamara

------------------

- Github issue 49

- Github issue 64 - skip meaningless chunk of 4 zero bytes between two
otherwise-valid BIFF records

- Github issue 61 - fix updating of escapement attribute of Font objects read
from workbooks.

- Implemented ``Sheet.visibility`` for xlsx files

- Ignore anchors (``$``) in cell references

- Dropped support for Python 2.5 and earlier, Python 2.6 is now the earliest
Python release supported

- Read xlsx merged cell elements.

- Read cell comments in .xlsx files.

- Added xldate_as_datetime() function to convert from Excel
serial date/time to datetime.datetime object.

Thanks to the following for their contributions to this release:

- John Machin
- Caleb Epstein
- Martin Panter
- John McNamara
- Gunnlaugur Þór Briem
- Stephen Lewis