Enable Transmogrification item

[Helias]

Add a service to sell the transmogrification of (new) items that the players do not have -> this requries mod-transmog

In the website we need to implement a way to insert a valid ItemEntry to use for transmog.

The SOAP command that will be executed for this service will be:
.transmog characterGuid itemEntry -> this requires azerothcore/mod-transmog#75
(may we can ignore it during the web development)

Moreover, I would like to show the item dressed in a character of the current account logged-in with a 3D viewer -> this requires #105

[Helias]

mockup

[Helias]

azerothcore/mod-transmog#84