Pkg.installed add pkg verify

Add rpm verify option to pkg.installed state

```
    pkg_verify
        For requested packages that are already installed and would not be targeted for
        upgrade or downgrade, use pkg.verify to determine if any of the files installed
        by the package have been altered. If files have been altered, the reinstall
        option of pkg.install is used to force a reinstall.  Types to ignore can be
        passed to pkg.verify (see example below).  Currently, this option is supported
        for the following pkg providers: :mod:`yumpkg <salt.modules.yumpkg>`.

    Examples:

    .. code-block:: yaml

        httpd:
          pkg.installed:
            - version: 2.2.15-30.el6.centos
            - pkg_verify: True

    .. code-block:: yaml

        mypkgs:
          pkg.installed:
            - pkgs:
              - foo
              - bar: 1.2.3-4
              - baz
            - pkg_verify:
              - ignore_types: [config,doc]
```