async: split long filter_options line for readability
ruby_tasks: fix exception handling in TaskContext.new if the exception is thrown before local_task gets created
ruby_tasks: do not load the ruby process manager with ruby_tasks

The process manager is really a seldom-used feature, so require
the user to explicitly load it.
ruby_tasks: make the ruby_process_server argument optional in Process

It is only used to announce process stop, so there is really no need
to make it mandatory
documentation
ruby_tasks: rename badly named file deployment.rb to process.rb

The class was already called Process
properly deprecate the old process server / ruby tasks class names

I use the autoload feature to load a deprecation file that warns about
the new names, and then alias the old names to the new names. This keeps
the deprecation localized while still warning the user.
test,async: minor fixes