Fixes in bat scripts to enable running when sorcer is installed in a path with spaces
extract method to name threads using current thread name as a prefix
ExertionDispatcher: remove unused code
ExertDispatcher: don't implement Exec
ServiceProvider: replace 'this instanceof' with polymorphism
remove redundant code
fix misleading method name
fix spacer if called as jobber;
remove unused ComplexExertion
remove exception on empty job