Improvements and unnecessary steps cleanup

* remove prepare cordova-lib and link cordova-lib steps from cli_steps group since `coho npm-link` do the same job
* remove build_cordovajs_steps and copy_cordovajs_steps since this routines is handled by mobilespec now
* remove unused writejson.js file
* remove whitelist rules removal logic from updateconfig.js since windows platform handles whitelists correctly
Fixes some of PEP8 issues