0.17.0

Features:

• #441 - Single account multiple workers
• #682 - Add tests for Relative Orders

Changes:

• #588 - Refactor Staggered Orders place_closer_order allow_partial
• #663 - Run some mandatory tests in Travis

Fixes:

• #596 - Fix BitsharesOrderEngine and BitsharesPriceFeed inconsistent attributes
• #649 - Fix limit max balance to be used per asset, insufficient balance error
• #651 - Fix Staggered Orders bug in pytest.approx
• #664 - Fix DEXBot failed to ping node in Docker
• #668 - Fix KOTH bot trades with itself if spread is 0
• #670 - Fix KOTH with one asset

NOTE:
In case problems with OSX version, try out the 0.17.1 release which uses Python 3.7

Contributors:
@bitfag, @bitProfessor, @joelvai