v0.6.7

Minor stability release.

Minor changes:

• [CORE] make sure to flush the candle batcher, fix #2329 (#2482 - @askmike)
• [CORE] Add Tulip and Talib Indicator-Results to 'stratUpdate' event (#2483 - @H256)
• [CORE] Include STDDEV tulip indicator (#2485 - @H256)
• [GB] fix race condition regarding order cancellation (#2496 - @askmike)
• [CORE] Bugfix IPC communication regarding CP eol (#2500 - @alexvandervegt)
• [GB] Added ETC pairs to GDAX (#2501 - @crypto49er)
• [GB] Kraken stability improvements (#2502, #2536 - @askmike)
• [DB] Fixes empty client on postgresql plugin (#2504 - @alexvandervegt)
• [CORE] Add market and strat info to a backtest export (#2509 - @hiyan)
• [CORE] hotfix: dont close the stream until async indicators are done (#2533 - @askmike)
• [GB] hotfix: fix minimum doge ordersize on GDAX (#2539 - @askmike)
• [PLUGIN] Improved pushbullet messaging (#2549 - @RJPGriffin)
• [DOCS] Added descriptive comments for tulip indicators (#2564 - @botsedge)
• [UI] Fix to importer dates to UTC (#2566 - @rkingy)
• [UI] Improve transpiling of shared front/backend code (#2573 - @eusorov)
• [STRAT] if no strategy.historySize found, than get it from tradingAdvisor (#2548 - @eusorov)
• [GB] hotfix: Fixed fee calculations for binance exchange (#2578 - @olexiyb)
• [GB] Add new GDAX markets, update minimal trade sizes & make kraken markets dynamic (#2591, #2597, #2606 - @g1tt)
• [DOCS] Document current installation situtation & improve folder navigation commands (#2599 - @hiyan)
• [REPO] Add stale bot to manage issues (#2608 - @askmike)