Set Application to use postgreSQL.

Signed-off-by: Joseph Gabriel Zafra <joseph.zafra@gmail.com>
Added Strong_parameters to the gemfile.
Added Item Crud.

The item crud manages the items entered in the system.
Each item has a corresponding price that will be used when
the customer bills out.
Removed users model.

This was a test which was accidentally included in the commit.
Removing it to be safe.
Use simple_form gem to create our forms

Signed-off-by: Jess Malvin Chin <jess@teamcodeflux.com>
Merge pull request #3 from jmalvinchin/item-crud-simple-form

Use simple_form for our CRUDs