GNU Aris -- TODO List

* Interoperability with Isabelle - in progress.
* Rules.
  TESTING
  * co
  * id
  * bv
  * pr
  * lm
  * sp
  * dt
  * nq
* Subproofs - copying.
* Documentation
  * Rules
  * Keybindings
  * Basic Usage
  * Sequence Logic
* Subproof bug, crashes when ~10 subproofs are made.
* Grade flag.
* Specify file name in goal title bar.
* On Windows, connectives don't show up, might be a Windows problem.
