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Is your feature related to a problem? Please describe it.

Describe the solution you would like.

It would be nice to have a neater representation of the model objects - metabolites, reactions, genes, etc. For example,

This introduces a _repr_html_ within the DictList object. Each Object then declares a _DF_ATTRS internally that contains the needed column list for the data frame representation to be created. Adding a to_dataframe() function to DictList would solve this.

>>> model.reactions.to_dataframe()

I've currently already had this implemented at https://github.com/achillesrasquinha/cobrapy/tree/feats

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