fix range

[femtotrader]

Hello,

With Julia 0.7 we have the following depwarns

┌ Warning: `range(start, step, length)` is deprecated, use `range(start, step=step, length=length)` instead.
│   caller = range(::DateTime, ::DatePeriodFrame{Day}, ::Int64) at TimeFrames.jl:270
└ @ TimeFrames ~/build/femtotrader/TimeFrames.jl/src/TimeFrames.jl:270

It will be great if FemtoCleaner could fix it automatically.

From femtotrader/TimeFrames.jl#47 (review) pinging @iblis17

Kind regards