feat(ahk): add support for ahk2

Some users prefer to use AutoHotKey v2, so this commit adds a check for
both komorebi.ahk and komorebi.akh2 files, and the corresponding AHK
executables, whenever commands around configuration loading are run (on
startup, when manually reloading, and when watching for changes).

If both files exist in the home directory, komorebi.ahk will be
preferred (at least until AHKv2 is out of beta).

An example of a configuration file compatible with AHKv2 by @crosstyan
has been added to the documentation.

resolve #10

README.md

@@ -108,6 +108,11 @@ Once `komorebi` is running, you can execute the `komorebi.sample.ahk` script to
 If you have AutoHotKey installed and a `komorebi.ahk` file in your home directory (run `$Env:UserProfile` at a
 PowerShell prompt to find your home directory), `komorebi` will automatically try to load it when starting.
 
+There is also tentative support for loading a AutoHotKey v2, if the file is named `komorebi.ahk2` and
+the `AutoHotKey64.exe` executable for AutoHotKey v2 is in your `Path`. If both `komorebi.ahk` and `komorebi.ahk2` files
+exist in your home directory, only `komorebi.ahk` will be loaded. An example of an AutoHotKey v2 configuration file
+for _komorebi_ can be found [here](https://gist.github.com/crosstyan/dafacc0778dabf693ce9236c57b201cd).
+
 If you are experiencing behaviour where
 [closing a window leaves a blank tile, but minimizing the same window does not](https://github.com/LGUG2Z/komorebi/issues/6)
 , you have probably enabled a 'close/minimize to tray' option for that application. You can tell _komorebi_ to handle