org.apache.felix.utils.properties will save key=value on top of comments if the original properties file are all comments

for example if the properties file looks like

#
# just a comment
#

then if we add a property into this file and save it we get something like

key1 = value1
#
# just a comment
#

we should get

#
# just a comment
#
key1 = value1

instead