Puppet performance tuning

Reports about puppet compilation failures are getting more common - especially on puppet master itself and `stream2` and `db5`.

Suspected sub-optimal configuration of the puppet agents (and the timing the run with)

In this graph you can see the load spikes all 10 minutes:
![screen shot 2014-07-16 at 09 06 02](https://cloud.githubusercontent.com/assets/1888714/3595640/560976d4-0cb8-11e4-8d0d-fc37b33e1424.png)


Suggestions:
- Add `pluginsync = true` everywhere (http://docs.puppetlabs.com/references/latest/configuration.html#pluginsync - Default is supposed to be true?)
- Add `splay = true` (http://docs.puppetlabs.com/references/latest/configuration.html#splay) - Random delay before run
- Add `splaylimit = 5m` (http://docs.puppetlabs.com/references/latest/configuration.html#splaylimit) - default being the interval time set (our: 10 min)