2.8.7

Merge pull request formio#97 from formio/added-form-factory

Adding form factory.

Merge pull request formio#96 from formio/build-2.8.5

Fixed issue with button custom events.

Merge pull request formio#95 from formio/fixed-datagrid-problems

Fixed datagrid panels.

Updated docs.

Upgrade version to fix submit button handler.

Upgrade versions.

Merge pull request formio#86 from formio/multi-page-forms

Adding multi page forms.

Updated docs.

Fixed issues with the disabled flag not being consistent causing issues.