Use no-daemonize and not forking service

Making puppet fork and systemd to read PID file seems unnecessary complicated.
Adding dependency on puppetmaster to puppet

Sounds like a good idea to wait with start of puppet agent to finish starting
of puppet mater first.
Make relation between service and sysconfig file obvious

There is puppet service but it's environment file is called puppetagent
(probably due to historical reasons). Making the naming more consistent and
obvious.
Reading even old sysconfig file

For compatibility reasons reading even the old sysconfig file although new one
overrides it. But people who have some interesting settings in the old
sysconfig file can still use them unless the are set to something else in the
new one.
Merge pull request #2510 from miska/master

Little bit of systemd unit files polishing