Feature: Simplify MapScripts

[Philipp AUER]

Currently in order to use the Gen III MapScript feature one has to use a raw statement.

Since each map has to have at a MapScript header even if it is empty, it would be nice to have support for that from PoryScript.

One way to go about this could be, to define the MapScripts directly inside a dedicated environment, which could look like

mapscripts MyMap_MapScripts {
    mapscript MAP_SCRIPT_ON_TRANSITION {
        lockall
        ...
        releaseall
    }
}

and would compile to the MapScript header as well as the individual scripts defined in it, or an empty header blob.

MyMap_MapScripts::
    map_script MAP_SCRIPT_ON_TRANSITION MyMap_MapScripts_mapscript1
    .byte 0

MyMap_MapScripts_mapscript1:
    lockall
    ...
    releaseall
    return

[Marcus Huderle]

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