XD-1831 Mask Database Passwords

* Add module option type `Password`
* In `JdbcConnectionMixin` - Change password property from `String` to type `org.springframework.xd.module.options.types.Password`
* In `DetailedModuleDefinitionResourceAssembler` mask default password module option
* In `JobsController#list()` return PagedResources<JobDefinitionResource> that contain masked passwords in the job definitions
* Create AngularJS directive `xdFormatStream`
* Create unit tests for AngularJS directive `xdFormatStream`
* In `module-create-definition.js` make sure the option type is correctly set
* In `definitions.html` make sure the `xd-format-stream` directive is called
* In `module-create-definition.html` set the form input field to type password, if the module option type is `Password'
* In `module-create-definition.html` set the form input field to be a checkbox, if the module option type is `boolean`
* Add E2E tests `create-new-definition.spec.js`
* In `module-create-definition.html` apply the xd-format-stream directive when outputting the `calculatedDefinition`
* Add `lodash` JS library
* Add Java utility class `org.springframework.xd.dirt.stream.util.StreamUtils`
* Add `StreamUtils#maskPasswordsInStreamDefinition`
* Add unit tests for `StreamUtils#maskPasswordsInStreamDefinition`

Jira: https://jira.spring.io/browse/XD-1831
Implemented with latest commit. Also added unit tests to underline the importance that solely the `password` value must be returned by `toString()`.