Modified all create/save/updateOrCreate to support parameterized queries.  This will eliminate the SQL Injection attack and also provide better handling of data types and nulls.  Moved string concatenations to array push to improve performance.
Merge branch 'master' of github.com:kesavkolla/loopback-connector-postgresql into kesavkolla-master

Conflicts:
	lib/postgresql.js
Merge branch 'kesavkolla-master' into feature/fix-pr-9
Extract property names in _categorizeProperties()
Merge pull request #10 from strongloop/feature/fix-pr-9

Feature/fix pr 9