Fixed failing tests in LinkRedirectionService
LinkService: Support decimal unicode-points

Decimal unicode points of the format &#8212; (which is the html decimal
numeric representation of the em-dash character) will now also be decoded
in page titles.

Closes #8
Requires Tests (#9)
LinkService: Add support for hex code points

See also #8, #9, and a85d2b8
LinkService: Merge entity parsing routines

The HTML standard entity parsing loop has been removed in favour of using the
matcher find/append pattern. The entities are currently treated as all numeric;
if a NumberFormatException occurs, the entity is then checked against the
mapping list.
LinkService: remove exceptional coding pattern

The check for whether an entity is numeric or not is now done by searching for
the required leading # character. This removed the need for both using a
try/catch block as a logic condition, and also the re-evaluation of the entity
group.