Refactor user path references

[elikem]

/lib/assests/mystorybooklet-english /storage/users/userid[number]/time-stamp_publication-number

Helper methods

• create_folder
• delete_folder
• create_user_folder
  • storage/users/userid[number]
• create_publication
  • storage/users/userid[number]/time-stamp_publication_number
• create_idml
• publication_folder
• publication_filename
• constants
  • story_title_template
  • drop_cap_template
  • story_content_template
  • mystorybooklet_template_folder