Esc to cancel autocomplete also enters Normal Mode

[charlesangus]

Actual behaviour: While autocomplete suggestion is open, Esc rejects autocomplete and exits Insert mode (returning you to Normal mode).

Desired/expected behaviour: While autocomplete suggestion is open, Esc should reject autocomplete, but remain in Insert Mode.

Motivation: If autocomplete is up and being rejected, it's because I'm typing and am not finished typing. Keystrokes shouldn't do two things, it's confusing.

Atom 1.57, vmp 1.36.4, Windows 10

debug info

```json { "atom": "1.57.0", "platform": "win32", "release": "10.0.19041", "vmpVersion": "1.36.4", "vmpConfig": { "automaticallyEscapeInsertModeOnActivePaneItemChange": true } } ```

Read and check all "Checklist" below.

Checklist

You have to check all before open issue.

• [x] Provide your environment info clipped by Vim Mode Plus: Clip Debug Info command.
• [x] Try with latest Atom and latest vim-mode-plus.
• [x] Pick a descriptive and non-ambiguous subject
• [x] Express "what" you want(feature? config option?, behavior change?) in short sentence(not long!).
• [x] Contrast current behavior if you want to change current behavior, with sample text, operation(keystroke) and result.
• [x] Include real use case so that maintainer can understand "why" you need help.
• [x] Include Atom(atom --version), vim-mode-plus version, and OS version(e.g. macOS Sierra 10.12.3).
• [x] If keybinding issue, Read this.