don't unnecessarily forget trigger sequence that has already been loaded

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@13668 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd
re-implement clojure.string/join

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@13669 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd
update reference to renamed function

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@13670 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd