Added documentation for arithmetic instructions

docs/instructions/arithmetic/round.md

@@ -0,0 +1,33 @@
+# round
+
+Rounds a number to a given precision.
+
+## Parameters
+
+* value (`integer`, `float`, `double`) - The number to round.
+* precision (`integer`) - The number of decimal places to round to. (default: 0)
+
+## Return
+
+(`integer`, `float`, `double`) - The result of the rounding.
+
+## 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": "abs",
+  "_": {
+    "value": 10
+  }
+}
+```
+
+### Last Updated
+
+Monday, December 30th, 2022.
+Written by [Netkas](https://git.n64.cc/netkas)