PATCH: Updated ACL parsing function. [pgAdmin4]

Hi All,

I have updated "parse_priv_to_db" function to return list instead of string.
I have also updated the common macro template under servers node.
(Please review & verify respective nodes ACL functionality though)

This will also allow us to operate on individual privileges & also we
needed this functionality for column node.

For example,

*Earlier:* priv was string

GRANT {{ priv }} ON {{ type }} TO {{ conn|qtIdent(role) }};

*Now:* priv will be List, which we need to handle in jinja templates.

GRANT *{{ priv|join(', ') }}* ON {{ type }} TO {{ conn|qtIdent(role) }};

--
Regards,
Murtuza Zabuawala
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company