Fixed #3127 (Shotwell fails to build on trunk), replacing a non-portable echo command with printf.
Fixed #3127 (Shotwell fails to build on trunk), replacing a non-portable
echo command with printf.


jof/shotwell,damianmoore/shotwell,Sanva/shotwell-gsoc,Sanva/shotwell-gsoc,ritchiewilson/shotwell,jof/shotwell,jimbonator/shotwell,damianmoore/shotwell,polymeris/shotwell,abrauchli/shotwell,abrauchli/shotwell,h4ck3rm1k3/shotwell,jimbonator/shotwell,abrauchli/shotwell,ritchiewilson/shotwell,h4ck3rm1k3/shotwell,h4ck3rm1k3/shotwell,Sanva/shotwell-gsoc,ritchiewilson/shotwell,jof/shotwell,jimbonator/shotwell,polymeris/shotwell,damianmoore/shotwell,polymeris/shotwell