chore(core/ElementRegistry): pull API changes

Related to #153
feat(palette): migrate to icon font

Related to #148
chore(icons): update font
chore(dependencies): upgrade karma-bro -> karma-browserify
feat(drop): add BPMN rules for drop

See #127
refactoring(rules): move rules from modeling to rules service

See #127
feature(drop): Support for drop of shapes into container shapes
fix(rules): update to master changes