Configure a dynamic hard eviction target in memory pressure situations

[simonswine]

Is this a BUG REPORT or FEATURE REQUEST?:

/kind feature

What happened:

Currently tarmak's kubelets are configured to do a hard eviction based on kubelets default memory target of 100Mi.

What you expected to happen:

We should have a memory hard eviction target configured based on the full node's memory (e.g. 5% of the available memory

Anything else we need to know?:

Puppet has the available node memory in so called facts and they can be used to determine that configuration option.

[simonswine]

Fixed in #150