pgAdmin 4 commit: Ship with pre-configured paths that can work in both

Ship with pre-configured paths that can work in both Server and Desktop modes out of the box. Fixes #2662

Ship the web code using server mode with appropriate paths by default and enable the runtime to override the mode, and force into desktop changing the appropriate paths to user-specific ones.

Note that this change will likely cause more advanced users to have to tweak configs.

RPMs will also need changes to create /var/lib/pgadmin and /var/log/pgadmin, owned by the webserver account.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=f195b18f2d9145592ae60c55840405dc3dfc8ea6

Modified Files
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runtime/Server.cpp | 3 +-
web/config.py | 106 +++++++++++++++++++++++++++------------------
web/pgAdmin4.py | 11 +++++
web/regression/runtests.py | 11 +++++
4 files changed, 89 insertions(+), 42 deletions(-)