Travis CI failing

[bvssvni]

src/physfs/mod.rs:123:17: 123:29 error: type `collections::string::String` does not implement any method in scope named `push_char`

src/physfs/mod.rs:123 err.push_char(c);

^~~~~~~~~~~~

Should use .push http://doc.rust-lang.org/std/string/struct.String.html#method.push