Reworked PasteItem tests (use ftw.testbrowser instead of OGBrowser).
Adjust available expression for paste action.

Use `object` instead of `folder` to call the `is_pasting_allowed`, because it's
not guaranteed that all folder allways returns the current context.
Disable paste action for mails.
Make sure metadata-fix profile is always installed last as policy-depencency.

The order specified in metadata.xml is not guaranteed, thus we hard-code
the depencency in the deploy class and install it once the policy has been
installed.
Merge pull request #665 from 4teamwork/pg_disable_pasting_for_mails

Disable pasting action for mails
Don't configure admin-unit twice, it is already done by the deployment.
Merge pull request #667 from 4teamwork/deif-fix-unit-creation

Don't configure current admin-unit twice.
Merge pull request #666 from 4teamwork/deif-mimetype-fix

Make sure metadata-fix profile is always installed last as policy-depency.
Reworked extract attachment tests.
Extract attachments view: fixed icon display in attachment listing.