Text that has been 'removed from path' is split on Enter (instead of linebreak)

[Hachmann]

Steps to reproduce:

- create a path
- create a text
- put text on path
- remove text from path
- double-click text to edit
- hit Enter to create a linebreak in text
- get: 2 text objects, split on the linebreak

(also, 'remove from path' sometimes places the text far away from its current position - can be hard to find it)

Inkscape 0.91 on LM 64bit, from official Ubuntu repos

[su_v (suv-lp)]

Reproduced with Inkscape 0.47, 0.48.5, 0.91 and 0.91+devel r14224 on OS X 10.7.5.

[su_v (suv-lp)]

<tspan> of the text object removed from path lacks attribute defining its role for Inskcape's text editing tool:

    sodipodi:role="line"