* use `timedelta64_to_secs` everywhere necessary * removed `max_sample_period` from all functions which can now use `insert_zeros`.  This has simplified the code quite a lot ;)
* use `timedelta64_to_secs` everywhere necessary
* removed `max_sample_period` from all functions which can now use
`insert_zeros`.  This has simplified the code quite a lot ;)

jaduimstra/nilmtk,pauldeng/nilmtk,josemao/nilmtk,AlexRobson/nilmtk,mmottahedi/nilmtk,HarllanAndrye/nilmtk,nilmtk/nilmtk,nilmtk/nilmtk