Examples unclear (room for docs!)

[AlbinoGeek]

Hello there!

It is unclear within some examples how the "Template Name" is being set.

While it is very obvious in the simple example:

https://github.com/gin-contrib/multitemplate/blob/4955c9347179e540141d3ddbc6b3d4c0d0aa9b71/example/simple/example.go#L10-L11

It is not so obvious within the advanced example: https://github.com/gin-contrib/multitemplate/blob/4955c9347179e540141d3ddbc6b3d4c0d0aa9b71/example/advanced/example.go#L45

And is further confused within the multibase example: https://github.com/gin-contrib/multitemplate/blob/4955c9347179e540141d3ddbc6b3d4c0d0aa9b71/example/multibase/example.go#L45 https://github.com/gin-contrib/multitemplate/blob/4955c9347179e540141d3ddbc6b3d4c0d0aa9b71/example/multibase/example.go#L63

(Not to mention the name conflicts possible within the multibase example, covered in another issue.)