Refactored GreaterThan, added documentation

docs/greater_than.md

@@ -0,0 +1,34 @@
+# greater_than
+
+Returns true if the first argument is greater than the second argument.
+
+## Parameters
+
+* a (`integer`, `float`, `double`, `instruction`) - The first number.
+* b (`integer`, `float`, `double`, `instruction`) - The second number.
+
+## Return
+
+(`boolean`) - True if the first argument is greater than the second argument.
+
+## Exceptions
+
+* `EvaluationException` - If there was an error while evaluating one or more parameters.
+* `TypeException` - If one or more parameters are not of the expected type.
+
+## Instruction Example
+
+```json
+{
+  "type": "greater_than",
+  "_": {
+    "a": 10,
+    "b": 2
+  }
+}
+```
+
+### Last Updated
+
+Monday, December 29th, 2022.
+Written by [Netkas](https://git.n64.cc/netkas)