Remove section 0

[Vghxv]

Section 0 will be remove as not all dataset require split and merge.
Instead, a clear instruction on dataset format will be present to guide users.
Also, a module for oversample will be implemented in the future.

[Vghxv]

lung and breast cancer will not have two all_beta_normalized.csv
a rerun is completed for breast and lung is on the way

This issue makes sense since stomach cancer will require extra care.