Bug Afx: Allow Eel to contain strings with unbalanced braces

[mhsdesign]

this for example wont work:

value = afx`
{"{"}
<Neos.Fusion:Loop items={props.properties}>
    {itemKey}: {item}
</Neos.Fusion:Loop>
{"}"}
`

and will transform to:

value = ${"{"}
<Neos.Fusion:Loop items={props.properties}>
    {itemKey}: {item}
</Neos.Fusion:Loop>
{"}"}

which makes the fusionparser upset and causes a non understandable exception.

--- i fixed that already locally out of fun once ... let me find it ^^