Support Tilde as dead key

[darodrigues]

The "Escaped Commands" section of the file src/classes/keyboard.class.js lacks a case "TILDE": which would set the property this.container.dataset.isNextTilde to true. As it is, even though the rest of the code required to use it is in place, it is impossible to use the tilde as a dead key.

[GitSquared]

Will look into this.

[GitSquared]

Thanks for spotting this!