Added subsys lock to worker init script.

This is required on RHEL style machines to properly handle run level changes.
Only create subsys in worker init when running as root
Merge pull request #47 from awiddersheim/worker_init_fix

Added subsys lock to worker init script.
remove pid for any user
improved dead worker detection
restart worker if there are no checks going on (fixes #41)

Add safety hook which restarts all workers if there where no checks in 2
minutes.  If thats the case, either the worker are broken or nagios is not
running and sending checks at all. In the second case, restarting the workers
doesn't hurt.
updated docs
be more verbose on errors
make full test more verbose
make waitpid child check optional
remove unused variable
more debug output on test errors
fix tests on freebsd9

dlerror() returns Undefined symbol "_nss_cache_cycle_prevention_function" so just
clear any errors before loading the neb module since we are only interested in
errors related to our neb module.
make tests more reliable
removed waitpid bullshit again
updated changelog
corrected debug output for use_uniq_jobs
tests: even more debug messages
updated readme
updated recommended gearman version