begin parser to load from file

fcore/parsing/parsing.md

@@ -0,0 +1,17 @@
+# Parsing
+
+The parsing functionality is for saving and loading from a custom file format.
+
+The BNF for the custom file format is below.
+
+Terminals are surrounded by `**` to the left and right. (rule)+ means "1 o more".
+
+```
+int ::= (0-9)+
+
+item ::= **{** int int int int int int int int **}**
+
+grid ::= int int **{** (item)+ **}**
+```
+
+The large number of `int`s in the `item` always follows the order: `x y ex ey r g b a`.