Improve handling of misused type hints in the console

[aroberge]

Using : instead of = results in adding a type hint instead of assigning a value. With recent improvements to friendly-traceback, this is handled reasonably well in a regular interactive session as shown below from friendly_idle:

Using the friendly console, a warning is displayed, but the information about the type hint is removed, and is no longer available when an exception is raised

Improvements:

• [x] Keep warning but also keep the information. This will likely require a fair change in the logic.
• [x] Remove the invitation to comment about warnings, and close that issue.

[aroberge]

Here's the result:

[aroberge]

Reopening this issue as it keeps issuing warnings if type hints have been added to a builtin.