dist: rename dist/ubuntu to dist/debian

Now we supported both Ubuntu and Debian on dist/ubuntu, and Ubuntu is one of
Debian variant, so dist/debian is better naming.

Signed-off-by: Takuya ASADA <syuu@scylladb.com>
Message-Id: <1486547332-3247-1-git-send-email-syuu@scylladb.com>

dist/debian/build_deb.sh

@@ -1,6 +1,6 @@
 #!/bin/bash -e
 
-if [ ! -e dist/ubuntu/build_deb.sh ]; then
+if [ ! -e dist/debian/build_deb.sh ]; then
     echo "run build_deb.sh in top of scylla dir"
     exit 1
 fi
@@ -39,9 +39,9 @@ fi
 echo $VERSION > version
 ./scripts/git-archive-all --extra version --force-submodules --prefix scylla-jmx ../scylla-jmx_$SCYLLA_VERSION-$SCYLLA_RELEASE.orig.tar.gz 
 
-cp -a dist/ubuntu/debian debian
-cp dist/ubuntu/changelog.in debian/changelog
-cp dist/ubuntu/rules.in debian/rules
+cp -a dist/debian/debian debian
+cp dist/debian/changelog.in debian/changelog
+cp dist/debian/rules.in debian/rules
 sed -i -e "s/@@VERSION@@/$SCYLLA_VERSION/g" debian/changelog
 sed -i -e "s/@@RELEASE@@/$SCYLLA_RELEASE/g" debian/changelog
 sed -i -e "s/@@CODENAME@@/$CODENAME/g" debian/changelog