`prop.readOnly false` should not generate the `readOnly` attribute

[MangelMaxime]

Similarly to #81, if you set prop.readOnly false in an input then the input has the readonly attribute making it read only.

Html.input [
    prop.value "Some text"
    prop.readOnly false
]

generates:

<input _svid="27" readonly="false" >

but the input cannot be edited.

Work around:

Html.input [
    prop.value "Some text"
    if false then // Condition
        prop.readOnly true
]

[davedawkins]

I did think I'd fixed this. Let me look into it.

[davedawkins]

Fixed in Sutil 2.0.14