Ctrl-z doesn't output correct Scenetrans setup code

[sebjameswml]

Especially 0 values come out as 0f rather than 0.0f.

Solution might be to output float{val}

[sebjameswml]

Example:

Scenetrans setup code:
    v.setSceneTrans (morph::vec<float,3>({0f, 0f, -3.5f}));
scene rotation is Quaternion[wxyz]=(1,0,0,0)
Writing scene trans/rotation into /tmp/Visual.json... Success.

[sebjameswml]

Fixed with 64b7cc8