added missing 'x' in hexadecimal escape example (#229)
added missing 'x' in hexadecimal escape example (#229)

The spec says that `\0A` as an escape sequence should evaluate to the newline character (`0x0A` in hex), when it is actually octal 0 followed by the character 'A'. I believe the spec meant to say `\x0A`, which does what is described.
bazelbuild/starlark,bazelbuild/starlark