feat(plugins-client/lib.apf/www/apf-packaged/apf_release.js): add excludeExtensions
feat(plugins-server): add lean runner
feat(plugins-client/ext.themes/themes.js): set current theme
feat(package.json): use leanprover/ace
feat(package.json): add architect-build dependency
feat(*): support '.lean' extension
feat(plugins-client/ext.noderunner/noderunner.js): add lean runner
feat(configs/default.js): load lean runner