pgAdmin 4 commit: Include a hash of the executable path in the lock and

Include a hash of the executable path in the lock and address file names.

This allows side-by-side running of different instances of the runtime.

While we're at it, improve some comments and tidy up a little.

Branch
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runtime-revamp

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=4910d10b35563428bfb5074d0303a6afc81af1e6

Modified Files
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runtime/pgAdmin4.cpp | 77 +++++++++++++++++++++++++++++++++++++++++-----------
runtime/pgAdmin4.h | 2 ++
2 files changed, 63 insertions(+), 16 deletions(-)