[dashboard] get rid of django-floppyforms dependency

As a workaround we can copy the code we want into murano-dashboard, although that requires some research.

The plan is:
1) remove floppy-forms from dashboard
    This will affect dynamic UI, but since we are introducing new version anyway - it's ok
2) replace floppy form usage during porting mysql app from app-incubator to murano-apps.
    this app is not working with the latest murano and it's needed only for that

Reviewed: https://review.openstack.org/198796
Committed: https://git.openstack.org/cgit/openstack/murano-dashboard/commit/?id=b21538e2a30b94a26db3f1c09f9c4897f41a2fea
Submitter: Jenkins
Branch: master

commit b21538e2a30b94a26db3f1c09f9c4897f41a2fea
Author: Kirill Zaitsev <email address hidden>
Date: Mon Jul 6 18:44:03 2015 +0300

    Remove unused and unsupported table field

    This commit removes any mention of table field from dynamic_ui and
    removes floppyforms from requirements.

    'table' field was introduced for MsSqlClusterServer service, that
    changed significantly since then and does not use table field anymore.
    See
    https://github.com/murano-project/murano-app-incubator/blob/master/io.murano.windows.SqlServerCluster/UI/ui.yaml
    for more details (even though the repository is deprecated).

    Since no app available today uses this type of field, and no tests exist
    for this type of field. There is no way to test, that it works correctly,
    therefore it is very hard to transfer critical parts from floppyforms to
    murano-dashboard.

    'table' field depends on django-floppyforms, which is not
    present in global-requirements, which is problematic and prevents us
    from enabling proposal bot in murano-dashboard.

    'table' field was never documented, so no documentation change is
    required.

    Change-Id: I638c722c2bdde411aaefa02f3d4027119de0e0bd
    Closes-Bug: #1468342