does not handle/understand line continuations

[aisch]

e.g.:

RUN\
 apt-get update -y &&\
 apt-get install -y python python-dev python-pip &&\
 pip install ansible==1.9.1 &&\
 apt-get clean autoclean &&\
 apt-get autoremove -y

will mark line RUN\ w/ _Unknown instruction: RUN_ but this is all one line.

e.g.:

ENV ANSIBLE_EXTRA_VARS="\
spork_src_dir=/opt/spork\
"

will mark spork_src_dir=/opt/spork\ w/ _Unknown instruction: spork_src_dir=/opt/spork_.

etc.