Balzac1799

@zgpnuaa @qsyao @happydasch It seems that change [this line](https://github.com/happydasch/btplotting/blob/b3d72f212cc6b4fbdcbe3d30bcf2ff4125890c3d/btplotting/clock.py#L163) to `if c_start and c_start >= t_end` can fix the missing first candle error