Splits & multitasking

[curlpipe]

Being able to open multiple files in the same view together to work alongside each other.

This will lay the groundwork for more advanced features such as viewing diffs and a file tree.

• [ ] Use a tree-based structure for storing documents
  • [ ] store proportions
  • [ ] store list of documents
  • [ ] store "ptr" for each split (to represent the tab within that split)
• [ ] Render the splits on the screen
• [ ] Play nicely with the mouse feature
• [ ] Split commands and API in the configuration file (along with the user interface to control them)
• [ ] Vigorous testing with window resizing