feat: add pageUp/pageDown/home/end to SlickCellSelection

[ghiscoding]

• adding "pageUp/pageDown/home/end" to SlickCellSelection when using selection with "Shift+{key}"
• add new Example 19 demo to manually test updated Cell Selection feature w/wo Pagination

TODOs

• tested manually, it should expect the following:
  • doing pageDown twice then pageUp once should equal to 1 pageDown
  • doing Shift+Home from anywhere should select all cells from current position to first row
  • doing Shift+End from should select all cells from current position to last row
  • using Pagination and doing Shift+{key} should select cells in current page only and not outside of it
• add new Example to test Cell Selection with Pagination as detailed above
• add full unit test coverage
• add Cypress E2E tests

basic SlickGrid example

with DataView & Pagination example

[codecov]

Codecov Report

Merging #1126 (2fb523e) into master (82ba377) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master     #1126   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files          245       245           
  Lines        16847     16887   +40     
  Branches      6045      6063   +18     
=========================================
+ Hits         16847     16887   +40     

Files	Coverage Δ
...s/common/src/extensions/slickCellSelectionModel.ts	100.00% <100.00%> (ø)