Set +x on dbsc.Core.Antlr.Tests run_tests.sh.
Upgrade Antlr to 4.3.
Fix repositories.config.

msdbsc.Tests no longer exists, dbsc.Core.Antlr.Tests does.
Commit Antlr build support to the repo.

If it is not in the repo, fresh command-line builds fail
because the Antlr .targets file is attempted to be imported
but nuget package restore has not happened yet.
Upgrade Dapper 1.25 -> 1.29, just because.