pgAdmin 4 commit: Added functionality to Pause/Resume replay of WAL on

Added functionality to Pause/Resume replay of WAL on the database
server.

Tweaked a little bit by Ashesh.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=4dc7f84761d85c94657a17533ef34e96550c3998
Author: Neel Patel <neel.patel@enterprisedb.com>

Modified Files
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.../browser/server_groups/servers/__init__.py      | 166 +++++++++++++++++++--
.../servers/templates/servers/servers.js           | 119 ++++++++++++++-
2 files changed, 275 insertions(+), 10 deletions(-)