Install sqlalchemy-migrate from master if requested

Added possibility to install sqlalchemy-migrate from master instead of
pypi packages.

Change-Id: I8af92cbb03609799442b05db9772e3c82b76725b

Author: Ihar Hrachyshka

lib/stackforge

@@ -29,6 +29,7 @@ set +o xtrace
 # --------
 WSME_DIR=$DEST/wsme
 PECAN_DIR=$DEST/pecan
+SQLALCHEMY_MIGRATE_DIR=$DEST/sqlalchemy-migrate
 
 # Entry Points
 # ------------
@@ -40,6 +41,9 @@ function install_stackforge {
 
     git_clone $PECAN_REPO $PECAN_DIR $PECAN_BRANCH
     setup_package $PECAN_DIR
+
+    git_clone $SQLALCHEMY_MIGRATE_REPO $SQLALCHEMY_MIGRATE_DIR $SQLALCHEMY_MIGRATE_BRANCH
+    setup_package $SQLALCHEMY_MIGRATE_DIR
 }
 
 # Restore xtrace

stackrc

@@ -319,6 +319,10 @@ WSME_BRANCH=${WSME_BRANCH:-master}
 PECAN_REPO=${PECAN_REPO:-${GIT_BASE}/stackforge/pecan.git}
 PECAN_BRANCH=${PECAN_BRANCH:-master}
 
+# sqlalchemy-migrate
+SQLALCHEMY_MIGRATE_REPO=${SQLALCHEMY_MIGRATE_REPO:-${GIT_BASE}/stackforge/sqlalchemy-migrate.git}
+SQLALCHEMY_MIGRATE_BRANCH=${SQLALCHEMY_MIGRATE_BRANCH:-master}
+
 
 # Nova hypervisor configuration.  We default to libvirt with **kvm** but will
 # drop back to **qemu** if we are unable to load the kvm module.  ``stack.sh`` can