Support for multi-range row span values

• Added support for multi-range row span values, fixing issues caused by sheets that use them.

Improved Number Format Support

Breaking changes:

• Public-facing method "setCurrencyCode" has been removed, as the currency_code value had no effect to begin with.

Non-breaking changes:

• New configuration option "ReturnUnformatted". If set to true, cell values will be returned without number formatting applied. (Note: Date/Time values are still controlled by the "ReturnDateTimeObjects" option.)
• Number format parsing has been improved. The reader is now capable of parsing more complex number formats.
• General format now outputs cell values as-is, instead of attempting to cast them to a float.

Support for negative date/time values

• Fixed issues regarding negative date/time values, causing very early date definitions to lead to unexpected errors.
• Fixed number formatting not being applied in all expected cases.

Fix empty shared string issue

• Fixed a bug that caused empty shared strings to be treated incorrectly under certain conditions.

Fixes regarding custom formats and PHP 7.3 support

• Fixed a bug that caused cell formats making use of currency strings and language ids to break.
• Fixed a "continue in switch" warning in PHP 7.3.

Alphabetical column indexes and fixes

• Added the option to use alphabetical column names (A, B, AA, ZX) instead of numeric indexes in returned row contents, using the parameter "OutputColumnNames".
• Fixed a bug that caused leading zeros in text cell content to get removed if the cell was set to text via an apostrophe prefix.

Fix empty row handling issue

This is a bugfix release fixing an issue that prevented empty rows from being properly output in all appropriate cases.

Fix format handling issues

This is a bugfix release fixing an issue that caused format parsing to cease working for some files.

Improved handling of DateTime values and temporary files

• New configuration parameters to control automatic re-formatting of found Date/Time values: forceDateFormat, forceTimeFormat, forceDateTimeFormat
• Improved handling of potential errors when working with subdirectories of the configured temporary directory
• Fixed composer.json lacking ext-xmlreader requirement

Improved XML Namespace support

• Improved support for different XLSX file generators:
  • Improved awareness of XML namespaces.
• Improved support for newer OOXML editions:
  • Namespace URIs from newer versions of the OOXML standard are now recognized and handled accordingly.
• Dropped requirement for SimpleXMLElement.
• Minor improvements in handling used document resources.