[Mod] new seq

appveyor.yml

@@ -17,9 +17,10 @@ environment:
   MYSQL_PWD: Password12!
 
 install:
+  - python -m pip install --upgrade pip wheel setuptools
+before_build:
   - ps: psql -d "postgresql://$ENV:VNPY_TEST_POSTGRESQL_USER:$ENV:VNPY_TEST_POSTGRESQL_PASSWORD@localhost" -c "create database vnpy;"
   - ps: . "C:\Program Files\MySQL\MySQL Server 5.7\bin\mysql" -u $ENV:VNPY_TEST_MYSQL_USER -e 'CREATE DATABASE vnpy;'
-  - python -m pip install --upgrade pip wheel setuptools
 
 build_script:
   - pip install psycopg2 mongoengine pymysql  # we should support all database in test environment