Adding /script download (#826)

This reverts commit e98adb77a52d1e274ec320e0cafab34b24c1c738.

* First attempt at creating download system...

* Last try, I had uncommitted changes which I forgot to add.

If it fails now i swear imma delete my fork of fabric carpet.

* OK, this is the last chance. I have checked and double checked, this should not fail.

Todo make them more detailed, Im not the best person to do that tbh...

* Towards a suggestion builder

(Also committing stuff in ScriptDownloader incase it crashes)

* Finished first theoretically functional draft of suggestion builder

* improving suggestion building with actual github api

* Collapsing identical error messages

* Got suggestions to work!

Now gotta get the actual file to save to disk properly

* replacing whitespace with url whitespace to make it read form 'creativ building tools' etc

* Successfully downloaded script into folder location!

* only clients can access global scripts folder, so don't want to cause error message

* Compacting code and updating docs

* Fixed getting folders from file names

docs/scarpet/api/ScriptCommand.md

@@ -167,3 +167,11 @@ This would slow down the computation of fib(40) from a minute to two, but allows
 and be responsive to commands, using about half of each tick to advance the computation. Obviously depending on the 
 problem, and available hardware, certain things can take more or less time to execute, so portioning of work with 
 calling `gametick` should be balanced in each case separately
+
+# `/script download` command
+
+`/script download <global or local?> <path>` command allows to download and save scripts directly from [scarpet app store](https://www.github.com/gnembon/scarpet).
+You can choose whether to save the script in the global config scripts folder or the local per-world script folder, 
+(on servers it always saves in the scripts folder) and it will be saved there, e.g `/script download local survival/angel_block.sc`
+would save the `angel_block.sc` file [here](https://github.com/gnembon/scarpet/blob/master/programs/survival/angel_block.sc)
+to a folder called `appstore/survival` in the world's scripts folder.