Allow entities with numbers

Should allow both `&frac12;` and `$#189;` as well as regular entities.
Updating entity test source
Updating entity test output
Allowing hexadecimal entities too

Signed-off-by: RK <robert@woodst.com>
Adding test for hex-format entities

Signed-off-by: RK <robert@woodst.com>
Merge pull request #25 from rk/entities-patch

Allow &frac12; and &#189; format for entities