update design + fix small bug

Hello Anam vai,
I would be happy if you consider my pull reqest and/or give me a proper feedback. Followings are the changes i have made and you can see  my version here: http://leninhasda.net/manifestgen/

1# two column layout. i actually want to see whats happening in the mainfest file while making it =)
2# bug(??) fix: on current version if you add a icon it adds the icon path on manifest file. however if you remove the path and uncheck it, it doesn't remove the text from manifest file. fixed that
2# angular ui accordion added and some color change

Thanks