Revert "try to catch certain serious system exception as well"

This reverts commit 10d96e7a671a3a2b5a03e61cfec5ad97183393db.
Revert "reduce logs"

This reverts commit e2a1b083c3188918ebbaef97c60c06cd3ff31640.
Revert "minor style correction"

This reverts commit c6ff3c018b14c4156ea8e4f1130f26c41ac39f9b.
Revert "temp fix to the socket thread safe issue"

This reverts commit db7750cf1f8ce0fcb7a205422adf6fca127dc6a1.
Revert "log around remove socket"

This reverts commit 655cece2c1003a05f0e54ef88545cb8ce501c3e3.
Revert "avoiding mis-handling as symmetric NAT when running multiple vaults on same machine"

This reverts commit db43b5f2235fa958bd29dc54c2c090ca2e853c90.
Revert "log messages for tracking down the bad_alloc issue"

This reverts commit 911e0db3fa6996d54f0be8aa77e613d3e66b462e.
Backed out my original change to make Dispatcher not get deleted while it is being used in favour of Transport::Close() dispatching the connection teardown onto the appropriate ASIO thread instead.

Unfortunately this creates occasional deadlocks, so I disabled all ASIO multithreading, thus solving mutex brittleness in one fell swoop. If the performance hit isn't terrible I'm keeping ASIO single threaded.