added gulp plugins

Signed-off-by: gwendoux <gwenael.doux@cncc.fr>
updated gitignore

Signed-off-by: gwendoux <gwenael.doux@cncc.fr>
updated gulpfile

Signed-off-by: gwendoux <gwenael.doux@cncc.fr>
fixed layout

Signed-off-by: gwendoux <gwenael.doux@cncc.fr>
updated img

Signed-off-by: gwendoux <gwenael.doux@cncc.fr>