Survey

This release adds the ability for the user to specify a particular stdout/in for their prompts, making it much easier to write integration tests for their prompts as well as the standard ones provided by survey

This PR fixes some compatability issues with Ubuntu's terminal

This release adds support for Home, End and Delete keys. They work as expected on all supported terminals, even when the line overflows! Major thanks to stefanvassilev for this!

v1.5.0 added the ability to filter the options in Select and MultiSelect prompts, however it was relatively hidden to users who did not know of the feature. This caused a slightly confusing user experience when they typed as options would just disppear. This release attempts to address this by adding an instructional message alongside the help prompt, indicating that the user can type to filter as well as use the arrow keys to navigate.

This release adds the ability for the user to filter options in a Select and MultiSelect prompt to be filtered by typing. In order to not conflict with the ability to move the cursor with the `j` and `k` keys, that functionality is now toggled on by pressing `esc`.

This releases adds a few small improvements to survey:

* Fixed a bug that prevented `survey.Required` from allowing any response from a `survey.Confirm` prompt.
* the cursor in `survey.Select` and `survey.MultiSelect` can now be moved with j/k to emulate vim keybindings