Release 1.5.0

Lightwood 1.5.0 changelog:

Many thanks to this month's community contributors!
@alteregoprofile, @LyndonFan, @MichaelLantz, @mrandri19, @ongspxm

Features:

• MFCC-based audio encoder (#625, #638; @mrandri19)
• Quantum mixer (#645, @ongspxm)
• Identity encoders (#623; @LyndonFan)
• Simpler default splitter (#624)
• MeanEnsemble (#658; @mrandri19)
• Improved interface to predict with all mixers (#627)
• API: predictor_from_json_ai (#633; @mrandri19)
• One-hot encoder mode to work without unknown categories (#639; @mrandri19)
• System for handling optional dependencies (#640)

Bug fixes:

• Img2Vec encoder bug fixes and tests (#619, #622; @mrandri19)
• Fix encoder prepare calls (#630)
• Black formatter fix (#650)
• Docs: doc_build triggers during pull_request (#653, #665; @MichaelLantz)
• ArrayEncoder fixes (#604, @alteregoprofile)

Other

• Rename fit_on_validation to fit_on_all (#626)
• Smaller test datasets (#631)
• Docs: add a time series forecasting tutorial (#635)
• Improved documentation coverage (#654, #660)
• Docs: doc_build automatically runs jupyter notebooks (#657)