Add 'lexer' feature to tutorial intro
So that the rest of the tutorial compiles and runs. Hopefully this will
be less confusing for people new to the project.
@@ -30,7 +30,7 @@ version = "0.1.0"
authors = ["Niko Matsakis <niko@alum.mit.edu>"]
[build-dependencies] # <-- We added this and everything after!
-lalrpop = "0.19.1"
+lalrpop = { version = "0.19.1", features = ["lexer"] }
[dependencies]
lalrpop-util = "0.19.1"
