Random sample data

[femtotrader]

Closes #27

[Arkoniak]

Is downward trend intentional? Maybe by default should be price_var_max = 1.0?

[femtotrader]

Fixed

[Arkoniak]

This one probably is a leftover?

[femtotrader]

Fixed also

[Arkoniak]

It would be nice to have tests, but for this it's better to add rng parameter in function signature.

For example:

using Random

function random_cl(rng::AbstractRNG = Random.default_rng();
    start = Dates.DateTime(2020, 1, 1),
    ... # all other fields

and use it internally with constructions like

price_init .+ cumsum(rand(rng, price_var_min:price_var_step:price_var_max, length))

I am not sure though, if it is possible to use Random.default_rng() in Julia versions prior to 1.9

For compatibility reasons, one can use Random.GLOBAL_RNG

[femtotrader]

Tests have been added
Should be ready now