[OE-4273] Initial work on zooming: added zoom icons and toggle state to drawing toolbar
[OE-4273] Setting the scale level dynamically
[OE-4273] Added grunt mocha, fixed tests, added additional tests for drawing scaling and related fixes
[OE-4273] UI fixes
[OE-4273] Fixed tests, removed debug, new dist files
[OE-4273] Removed TODO.txt
[OE-4273] Added option to set the toggleScale level. If set to 0, zooming feature will be disabled.
Merge branch 'feature/zoom' into release/1.7
Merge branch 'release/1.7' into develop