[FIX] stock_account: Flaky test due to Float Point inacuracy
Created by: nhomar
When run tests mixing some environment variables line Postgres 9.5.2 and Python 2.7.11+ (Ubuntu 16.04) and or Python 2.7.9 (Debian Jessie) this tests was giving different results because the tests is not using float_compare as it should.
Even if the method is correctly done the comparition in the test is incorrect.
