Allow the LegacyService to initialize in headless mode

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
ij-legacy: no need to skip tests in headless mode anymore

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Fix whitespace

Especially with vim or Git showing white space at the end of the line
as red, it could cause eye cancer. We do not want that to happen,
so let's remove it.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>