Load Required PostgreSQL Extension into Database

[vladimir-v-diaz]

I had to load "uuid-ossp" to successfully setup the project.

$ sudo -u postgres psql warehouse
psql (9.2.6)
Type "help" for help.

warehouse=# CREATE EXTENSION "uuid-ossp";
CREATE EXTENSION
warehouse=# \q

Should the development environment section include loading the "uuid-ossp" extension into the warehouse database? If not, executing "$ warehouse -c dev/config.yml migrate upgrade head" raises the following exception:

qlalchemy.exc.ProgrammingError: (ProgrammingError) function uuid_generate_v4() does not exist
HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
 '\nCREATE TABLE downloads (\n\tid UUID DEFAULT uuid_generate_v4() NOT NULL, \n\tpackage_name TEXT NOT NULL, \n\tpackage_version TEXT, \n\tdistribution_type distribution_type, \n\tpython_type python_type, \n\tpython_release TEXT, \n\tpython_version TEXT, \n\tinstaller_type installer_type, \n\tinstaller_version TEXT, \n\toperating_system TEXT, \n\toperating_system_version TEXT, \n\tdownload_time TIMESTAMP WITHOUT TIME ZONE NOT NULL, \n\traw_user_agent TEXT NOT NULL, \n\tPRIMARY KEY (id)\n)\n\n' {}

[vladimir-v-diaz]

Reference issue #166.