[debian] Add depends on libjs-underscore for pycassa-doc

Fix lintian warning « embedded-javascript-library »
for usr/share/doc/pycassa-doc/manual/_static/underscore.js
Refer to Debian Policy Manual section 4.13 (Convenience copies of code)

debian/control

@@ -29,7 +29,7 @@ Description: Client library for Apache Cassandra
 Package: pycassa-doc
 Architecture: all
 Section: doc
-Depends: libjs-jquery (>= 1.4.2), ${misc:Depends}
+Depends: libjs-jquery (>= 1.4.2), libjs-underscore (>= 1.1.6), ${misc:Depends}
 Suggests: python-pycassa
 Description: Documentation for the Pycassa library
  Pycassa is a client library for Apache Cassandra with the following

debian/pycassa-doc.links

@@ -0,0 +1,2 @@
+/usr/share/javascript/jquery/jquery.js usr/share/doc/pycassa-doc/manual/_static/jquery.js
+/usr/share/javascript/underscore/underscore.js usr/share/doc/pycassa-doc/manual/_static/underscore.js

debian/rules

@@ -10,6 +10,7 @@ override_dh_auto_build:
 override_dh_install:
 	dh_install
 	rm debian/pycassa-doc/usr/share/doc/pycassa-doc/manual/_static/jquery.js
+	rm debian/pycassa-doc/usr/share/doc/pycassa-doc/manual/_static/underscore.js
 	ln -s /usr/share/javascript/jquery/jquery.js debian/pycassa-doc/usr/share/doc/pycassa-doc/manual/_static/
 
 override_dh_auto_install: