[request] non-singular logic and position components

[Tcll]

@AndrewWPhillips: I know you're not really working on this much, so this isn't exactly for you unless you want to. ;)
This is another request from the old forums, but I'm giving a bit better detail as to what's expected from it...

the idea is to use multiple tags in logic and jump tags, like so:

<struct>
    <data>
    <if>
        <data>
        <data>
    <else/>
        <data>
        <data>
        <data>
        <data>
    </if>
</struct>

what's expected from this is, if the test is true, the tree will only display this:

struct
    data
    data
    data

but if the test is False, the tree will display:

struct
    data
    data
    data
    data
    data

the same should apply to the jump tag, where the tags enclosed by it are dealt with at the new offset:

<struct>
    <data>
    <jump 64 current>
        <data>
        <data>
        <data>
        <data>
    </if>
    <data>
</struct>

should display:

struct
    data
    data
    data
    data
    data
    data

where the middle 4 data tags are read at the new location (not saying this is practical of course).

this will greatly reduce how painful it is to edit templates.