docs: document bool to_int and to_string methods
This documents the bool methods to_int and to_string implemented in
[1].
[1]:
@@ -93,6 +93,14 @@ A boolean is either `true` or `false`.
truth = true
```
+Booleans can be converted to a string or to a number:
+
+```meson
+bool_var = true
+string_var = bool_var.to_string()
+int_var = bool_var.to_int()
+```
+
## Strings
Strings in Meson are declared with single quotes. To enter a literal
