Password Input Field Support

[serenamarie125]

Create support for password input fields:
https://react-bootstrap.github.io/components.html#forms-layout

Include story examples demonstrating these features in a mock application scenario

Link to JIRA story:
https://patternfly.atlassian.net/browse/OSUX-349

[serenamarie125]

@sharvit would you mind assigning yourself to this, since you've already put up a PR ?! Thank you!