Update docs to reference both ways of returning entities

Closes josegonzalez/josegonzalez.github.io#3
Minor updates
Merge pull request #7 from jameswatts/patch-1

Minor updates
Use `$this->primaryKey` to ref table pk instead of hardcoded 'id'. Closes #8
add basic document for functions
support plugin Entity location
Merge pull request #9 from RitaCo/master

support Plugin entity location
Turn off entity creation by default. Closes #11
Override find('count') and find('threaded') to return arrays instead of Entities in all cases