pgAdmin 4 commit: Minimise memory requirements for rendered cells and r

Minimise memory requirements for rendered cells and rows in SlickGrid. Fixes #2035

- The CSS class 'slick-row' has been renamed to 'sr'

- The CSS class 'slick-cell' has been renamed to 'sc'

- The SQL Editor included an unused 'normal_row' class on each row which has been removed as it was unreferenced in the code or CSS.

The intent of these changes is to minimise memory usage by the grid, by saving a few bytes per row/cell.
It's questionable how much difference this actually makes given that SlickGrid updates the document so it
only includes the visible rows on the fly, but every little helps.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=87d49377261c9a6fa92bd19dc045740bc68eb701

Modified Files
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.../static/css/slickgrid/slick-default-theme.css | 20 +++++++++---------
web/pgadmin/static/css/slickgrid/slick.grid.css | 12 +++++------
web/pgadmin/static/js/slickgrid/README | 9 ++++++++
web/pgadmin/static/js/slickgrid/slick.grid.js | 24 +++++++++++-----------
.../tools/sqleditor/static/css/sqleditor.css | 14 ++++++-------
.../sqleditor/templates/sqleditor/js/sqleditor.js | 4 ++--
6 files changed, 46 insertions(+), 37 deletions(-)