fix: Partially revert project structure changes (#856)

Returns project structure to independent modules instead of parentage model, as original packaging scheme relies on this structure

Update README.md

Fixed formatting

Add parent, remove jsoup, fix artifact name

Delay and avoid expensive createCellDataForCell (#714)

Computing cell data shouldn't be done for all rows as it has a big
performance impact
With this change cell data is only created for sent cells and formulas

This change doesn't prevent the large json in some responses, but it
does prevent the extensive computing time on server-side which was
causing the 5 minutes time to first byte for the server request.
Fixes #713

Mark cells with formatting rules

Explicity import org.apache.poi.ss.formula #645 (#710)

Fix for issue #645
The import org.apache.poi.ss.formula is missing in the manifest. I have added an explicit import into the pom, which allows the spreadsheets.jar to run correctly on an OSGI server (such as Liferay 7.x)

Update spreadsheet version to 2.1.0 in tutorial (#695)

Fix NPE on widget clean (#693)

Fixes #691

Fix scroll when navigating to a cell (#686)

Fixes #664

Update repo url (#682)

Fix the new issues in 1.5 tests (#675)

Also fixes some imports and warnings