Including upstream requirements

Now that internal OSM software does not specify python modules in
setup.py, we need to include the requirements.txt from the module
in the requirements-dev.in to generate the full list properly.

Change-Id: I3b3eee1b7a88c4d0b14b7c8966769c3918ad77e0
Signed-off-by: beierlm <mark.beierl@canonical.com>
diff --git a/requirements-dev.in b/requirements-dev.in
index 620d427..49324f7 100644
--- a/requirements-dev.in
+++ b/requirements-dev.in
@@ -14,3 +14,4 @@
 # limitations under the License.
 
 git+https://osm.etsi.org/gerrit/osm/IM.git@master#egg=osm-im
+-r https://osm.etsi.org/gitweb/?p=osm/IM.git;a=blob_plain;f=requirements.txt;hb=master