pgAdmin 4 commit: Sporadically crashes on Windows when exit. Fixes#317

Sporadically crashes on Windows when exit. Fixes #3177
  1) Shutdown the python server properly.
  2) Disabled "Shutdown server" menu till server is not successfully started.

Initial patch sent by Maxim, modified by Akshay Joshi.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=54b1a79cb6f90ac9b26db57e616dc750fb2c6b54
Author: Maxim Zakharov <dp.maxime@gmail.com>

Modified Files
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runtime/Server.cpp           | 11 +++++++++++
runtime/Server.h             |  3 +++
runtime/TrayIcon.cpp         | 11 +++++++++++
runtime/TrayIcon.h           |  4 ++++
runtime/pgAdmin4.cpp         | 46 ++++++++++++++++++++++++++++++++++++++++++++
runtime/pgAdmin4.h           |  1 +
web/pgadmin/misc/__init__.py | 16 ++++++++++++++-
7 files changed, 91 insertions(+), 1 deletion(-)