Use puppet hash

The previous version was good when we have only 20 or so hosts. But with
some real infrastructure, the "one record means one puppet resource" is
a bit overkill.

Using the puppet hash allows us to provide only ONE puppet resource, and
make what we need in some ERB, making puppet a lot faster.

WARNING: this commit will BREAK your current configuration! Please read
embedded documentation and update your bind::* resources accordingly!
Record default template

As said, we're using hash - this template can understand them, and
provides a fast way to register many records.
Please see doc embedded in bind::records for hash structure.
bind::base - added required /etc/bind/pri directory
bind::a - updated in order to reflect bind::record
zone-header template - corrected $ORIGIN placement
Removed wrapper - please use bind::record, or make your own wrapper.

Why so?
- they are kind of useless now we're using hash
- they create more resources for nothing
Merge pull request #14 from cjeanneret/uses-hashes

Uses hashes