Added section for the target function change.
Auto-generate DiPy API reference
Update api tools to correctly summarize classes + functions. Render empty modules correctly. Fix TOC.
Allow api-clean to run, even if api hasn't been generated before
Require api build before html
Document api target
Fix now-defunct link
Merge pull request #356 from stefanv/feature/doc_generation

Auto-generate API docs
Changed the logo to cmomplete black as the one for the conference
Merge pull request #357 from Garyfallidis/web-logo

Changed the logo to full black as the one that I sent as suggestion for HBM and ISMRM
Merge pull request #355 from jchoude/add_target_break

DOC: Updated API change document to add target function change