pgAdmin 4 commit: Allow to specify the options as a function, which ret

Allow to specify the options as a function, which returns array in form
of (label, value) tuple in the SelectControl.

We will apply the transform function, while rendering the control, and
not during intialization. This will allow us to generate different
options data based on the dependent values.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=109b367fc31aa53e7022f11a04b4e1daddee9c90

Modified Files
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web/pgadmin/browser/static/js/node.ui.js  | 11 +++----
web/pgadmin/static/js/backform.pgadmin.js | 51 +++++++++++++++++++++++++++++++
2 files changed, 55 insertions(+), 7 deletions(-)