Make the prover work

This pull request relies on a few backwards-incompatible changes to Idris, thus it's after the 0.9.13 tag.
In particular, it needs https://github.com/idris-lang/Idris-dev/pull/1296.

New features/bug fixes:
 * When you complete a proof, Idris asks if you want to add it. If you say yes, it works like :addproof.
 * Semicolons are no longer used in proof script buffers
 * Keybinding in script buffers is M-n, M-p to work like REPL history
 * RET works in proof script buffers even if is next to read-only characters
 * Abandoning proofs no longer desynchronizes Idris
 * The prover remembers your window config and restores it after proving
 * The metavariable list contains buttons to launch the prover
 * Right-clicking metavar names in Idris output gives a menu that includes launching the prover
 * More functions and variables have doc 
 * The event log buffer contains readable timestamps for easier debugging