employers: move form to add an employer to it's own view

[MarchandMD]

Description

A clear and concise description of the issue.

the employers/index page should have a link to "add an employer" which connects to a form to add an employer. Moving the form currently on the index/ page is the goal

User Story

As a user
I want to add an employer by clicking a button on the index page
So that i'm taken to a new form to add an employer

Engineering Checklist

• add a button/link to the employers/index page to "add an employer"
• link to a new_employer view with a form
• move the form from employers/index to employers/new
• a new employer should be added/persisted to the list

Acceptance Criteria

• add a button/link to the employers/index page to "add an employer"
• link to a new_employer view with a form
• move the form from employers/index to employers/new
• a new employer should be added/persisted to the list

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Additional Context

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