Update reference

Author: vascocosta

docs/reference.md

@@ -19,7 +19,7 @@ Returns a record with all the functions exported by the module defined in file.
 ### `fn len(list: List): Int`
 Returns the length of a list.
 
-```python fn slice(list: List, start: Int, end: Int): List```
+### `fn slice(list: List, start: Int, end: Int): List`
 Returns a new list which is a slice of the list passed as argument, between index start and end.
 
 ## Module: `conv`
@@ -30,12 +30,15 @@ Returns a float by converting the string passed as argument.
 ### `fn int(string: String): Int`
 Returns an int by converting the string passed as argument.
 
-```python
-fn string(any: Any): String
-```
+### `fn string(any: Any): String`
 Returns a string by converting the type passed as argument into its string representation.
 
 ## Module: `env`
 
 ### `fn args(): List`
-Returns a list with all the command line arguments passed into the script.
+Returns a list with all the command line arguments passed into the script.
+
+## Module: `http`
+
+### `fn get(url: String): Record { error: Bool, value: String }`
+Returns a result record with a boolean error and the server response at url as a string.