fix accessibility issues with query grid

[alanrenmsft]

for #17452

1. In order to fix grid not getting the focus issue, I need to use the latest slickgrid but it is not compatible with the implementation as well as the angular2-slickgrid, I had to fix all the compatibility issues.
2. support change column width with keyboard, I followed the same pattern we implemented in ADS a couple weeks ago.
   

tested all the features:

1. selection
2. export
3. navigation with multiple grids