Repo needs a clean-up / fixes

[krrome]

kipoi-interpret needs a few fixes:

• The link to the tutorial doesn’t work in the main page
• The tutorial need to be rerun because the seqlogo part of the plots are wrongly defined.
• Return the ISM output as a list / dict of numpy arrays
• CLI re-design to make it modular
• support the reference input to DeepLIFT
• In-depth documentation