Class to read OpenDocument Tables
closes #2311 

This is primarily intended for LibreOffice calc spreadsheets but will
also work with LO Writer and probably with LO Impress documents.

This is an alternate solution to https://github.com/pandas-dev/pandas/pull/9070
There are test cases with several different problematic LibreOffice spread sheets.
git diff upstream/master -u | flake8 appeared to pass.

... I didn't do the whats new entry. Though I expect there's some more work to do before submitting this. I just wanted to get the core code in for comments.

The open issues is, the workaround for https://github.com/pandas-dev/pandas/issues/25422 is embedded in the current code (so all my tests pass right now) but that, or a better solution should move closer to the iso 8601 parser.

Also I don't have the parser class hooked up to a read_excel or read_ods function.

Using read_excel bothers me some... because its not an excel file. I think it would be more clear if there was either a separate read_ods function or a generic read_spreadsheet function than just pressing read_excel into being a generic spreadsheet reader.

Also this just a reader. I had never gotten around to implementing a writer.
