update documentation
update docs
bug in bibliographic_coupling
documentation
added builder for GraphCollections
docstrings
docstrings
Merge branch 'ramki_#60463750' into python
documentation
dfr.ngrams
started on matrices
Merge branch 'erick' into python
finished array and matrix methods for dfr
usage examples in docs
Merge branch 'erick' into python
added logo to docs
minor
Merge branch 'erick' into python
Merge branch 'python' into ramki_#60463750