project: light git and lein housekeeping

Tweaked various .gitignore files to keep the untracked
file list low.

Also added a min-lein-version to any unwary traveller
who might attempt to run the webfui-examples with lein1.
cleanup: removing a stray js output file

Removing what appears to be a stray cljsbuild output
file from the repo.
Merge pull request #2 from dribnet/master

Some light cleanup to repo and project.clj