Brasero string freeze break

[Philippe Rouquier <bonfire-app wanadoo fr>]

Hi (again),

Since this is just the announcement period, I'll try to make all string changes now =) (Gabor was right).
For the sake of coherence, I will change erase into blank so we use the same verb everywhere in brasero (burn-dvd-rw-format.c line 183 in master).

Thanks for your work all

Philippe