Prepare 0.20.3

Fixed notebooks

Bumpversion 0.20.1

Bumversion 0.20.0

Bumversion 0.19.0

Many thanks to core development team (@nils-braun and @MaxBenChrist) and all tsfresh contributers:
    - @abalhomaid
    - @abroekhof
    - @benman1
    - @jvdd
    - @mendel5
    - @OliEfr
    - @pfornia
    - @pnb
    - @solegalli
    - @tanlin2013
    - @wjsi

Bumpversion 0.18.0

Bumpversion -> 0.17.0

Version 0.16.0

Forgot to install the project on readthedocs...

Version 0.15.0