Non-descriptive thread name of resource releaser

[alamar]

software.chronicle.fix.demo.gettingstarted.example7.SendMessageAsDTO/disk~space~checker is a much better thread name than background~resource~releaser since it allows our user to understand who started this.

[peter-lawrey]

The backgroundresourcereleaser should be global and isn't expected to be stopped.

[alamar]

Unfortunately, exec:java will run a new every time, from a separate class loader.