Textnets version 0.7.0

• Adds abilitiy to save and load an instance of Corpus, Textnet and params to and from file using Corpus.save, tn.load_corpus,
  Textnet.save, tn.load_textnet, tn.params.save and tn.params.load. The same file can be used for all three kinds of objects, so all relevant data for a project can be saved in one file.
• Some further optimization of backbone extraction.
• Adds bipartite centrality measures (HITS, CoHITS and BiRank) and a bipartite clustering coefficient.
• Improved testing and type hints.
• Expanded documentation with advanced topics, including the new save/load feature and interacting with other libraries for network analysis and machine learning. Docs now use the PyData theme.
• Improvements to visualization. When plotting, nodes and edges can now be scaled by any attribute.
• Breaking change: Term weighing now happens in the corpus submodule, so the sublinear argument has to be passed to the methods for term extraction (tokenized, noun_phrases and ngrams). This change will make it easier to add additional term extraction and weighing options.
• Adds tn.init_seed() utility to quickly initialize pseudorandom number generator.
• Adds Python 3.10 compatibility.
• Updates dependencies, including igraph with some relevant upstream changes contributed by yours truly, as well as spaCy.