Add simplified syntax for external blocks

[SirLynix]

Allow variable blocks (currently only external blocks) to be declared inline.

[auto_binding]
external
{
   foo: uniform[Buffer]
}

=>

[auto_binding] external foo: uniform[Buffer];

Common attributes should be applied to both the block and the variable:

[binding(0), set(1), tag("MyBuffer"), cond(MyCondition)] external foo: uniform[Buffer];

will be understood as:

[binding(0), set(1), tag("MyBuffer"), cond(MyCondition)]
external
{
    [binding(0), set(1), tag("MyBuffer"]) foo: uniform[Buffer];
}

This is a syntaxic sugar that doesn't need any change to the AST.

[K-Tanish]

Hii
I can work on this issue
could you assign this to me

[SirLynix]

Hi, thanks for your enthusiasm, feel free to work on it and open a pull request.