Migrate prompt parsing logic to IPython.core.InteractiveShell

[osolmaz]

Currently, prompt parsing and interactive features such as package auto-installing, executing, etc. happen outside IPython parser. This has the following disadvantages:

• Prompts themselves are not stored in the history, but the Python code they resolve to
• The global and local namespaces have to be passed to ICortex.eval_prompt() in order to execute the Python code returned from services—if we implement the following steps, they can be accessed directly in the overloaded InteractiveShell

Steps:

• Create an overloaded version of IPython.core.inputtransformer2 and migrate prompt parsing logic in there
• Create an overloaded version of IPython.core.InteractiveShell which uses the overloaded inputtransformer2 and migrate interactive ICortex logic in there
• Modify ICortexShell to use the overloaded InteractiveShell

This will most likely simplify ICortexShell.do_execute() and resolve #10 automatically.

Possible issues:

• Will the interactive features (input() from the user) continue to work smoothly in both the shell and notebooks?