Additional transforms

[Avsecz]

• k-mer or gapped k-mer counter
• simple reverse complementation function

transforms/augmentation.py

• random sub-sequence augmentation
• random reverse-complementation

[Avsecz]

• experiment with using Numba to implement k-mer counting or other transforms. Have a fallback method if the user doesn't have numba installed locally

  try:
  import numba
  @numba.jit
  def kmers....
  except:
  def kmers