package.json: updated jshint version
jshintrc: removed option that become on by default
tasks/strip_code.js: full rework

new features:
 * user defined start/end blocks
 * support multiple patterns instaed of one
 * notify user if different amount of start/end blocks found
 * notify user if start/end pairs of different blocks intercept
Gruntfile.js: tiny fix for tests
updated README.md