pgAdmin 4 commit: Resolve various debugger quirks. Fixes #1227

Resolve various debugger quirks. Fixes #1227

- Prevent the user from executing multiple options at once, resulting in "Execute cannot be used while an asynchronous query is underway********** Error ****" messages

- Stop polling when debugging is complete.

- Don't show the busy cursory when debugging is complete.

- Display info messages properly, and reset them between executions.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=6f30cabdbb649cf852d33b76b676e2c966438235
Author: Murtuza Zabuawala <murtuza(dot)zabuawala(at)enterprisedb(dot)com>

Modified Files
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web/pgadmin/tools/debugger/__init__.py | 35 +++-
web/pgadmin/tools/debugger/static/css/debugger.css | 11 ++
.../tools/debugger/templates/debugger/js/direct.js | 183 ++++++++++++++++++---
3 files changed, 201 insertions(+), 28 deletions(-)