Only block keyup for keys where we have handled a keyup/press event

Fixes the issue of Vimium indiscriminately capturing keyup events,
introduced in PR #978.
Merge pull request #1130 from mrmr1993/fixKeyupCapture

Only block keyup for keys where we have handled a keyup/press event
Suggestion for impl of #1141
Changed key biding to use right arrow instead of tab, returning previous tab functionalities
Switching again to Ctrl+Enter
Allow passing of keys to the underlying page.
Allow passing of keys to the underlying page (minor code review).
Allow passing of keys to the underlying page (more minor code review).
Allow passing of keys to the underlying page (populate page popup with existing rule).
Allow passing of keys to the underlying page (fix/maintain order of exclusion list).
Allow passing of keys to the underlying page (slight reformatting of page popup).
Allow passing of keys to the underlying page (comments can start with " too).
New icons for partially enabled, for passkeys.
Better state management for passkeys.
Better icon for passkeys.
Do not call handlers which do not exist.
Do not call handlers which do not exist (fixed).
Do not call handlers which do not exist (fixed, again).
PassKey tests (1)
Fix passKeys bug introduced in commit 700d35a