feat: np.abs(df.x) and abs(df.x) now works, since it calls Expression.__abs__
feat: np.abs(df.x) and abs(df.x) now works, since it calls Expression.__abs__

maartenbreddels/vaex,maartenbreddels/vaex,maartenbreddels/vaex,maartenbreddels/vaex,maartenbreddels/vaex,maartenbreddels/vaex