Improving the repl

Most of the usability of dot notation comes from interactive use. Since JuliaLang/julia#1974 doesn't seem to be going anywhere soon, it would be useful to have a custom preparser in the repl. This would greatly enhance discovering class members and their documentation through tab completion.

I would like to help with this, but I do not know where to start.

Start by reviewing JuliaLang/julia#1974 and investigating how PyCall's REPL currently handles dot notation and tab completion. The work is complete when a custom preparser improves interactive discovery of Python class members and their documentation through tab completion.

索引モデルが issue の本文から書いたものです。