Update with multiple tags

[Jakob Hummes]

Hi all,

I've the following problem:

Say, I have a more or less stable version that I want to test, which I
tag with the tag "test_tag" on all files.

Now, one developer wants to test his new modifications, which are tagged
with "tag_developername" that are revisions after the "test_tag".

How can I update the local repository to compile all so that it contains
the following files:

All files with the "test_tag" revision and the revisions of all files
that are tagged with "tag_developername" .

TIA,
- Jakob