Support for different cursor shapes

[pinpox]

Currently on only the "block" cursor seems to be supported. When using vim, most terminals switch to the "i-beam" shape when in insert mode, it would be great if darktile could support different cursor shapes aswell and have this feature.

[liamg]

Good idea, I'll sort this next 👍

[liamg]

@pinpox I took it a step further and added support for images as cursors too :D

[pinpox]

😆