Support for multiple labels on a block of content

[nthiery]

Sometimes you want to have multiple labels for a given block of content. E.g. when that block defines several interrelated terms at once.

Proposal

Add support for:

(int)=
(integer)=
The type `int` let's you represent integers.

which defines two labels int and integer for the block of content. Currently, the label int is correctly set but not integer.

Thanks :-)