jsf.js: code restructuration for size and speed improvlements

Currently we have one big jsf.js file with all code in

• core which implements all of the spec
• i18n which implements the language messages for currently 7 languages
• experimental which implements features targetted for jsf 2.2 onwards
• quirksmode code which supports non standard compliant browsers

The idea is to still keep one big file, but also provide several files which partially can be mixed to achieve the functionality needed

We are going to allow

• one big file which resembles our current jsf.js
• a base file which resembles the core + quirksmode
• a modern browser file which resembles the core only without quirksmode code
• a separate i18n file for the i18n messages
• a legacy file for quirksmode browsers
• an experimental file with all non standard features combined
  In the end the plan is to allow the users to mix those feature sets to reduce the import size while still retaining all the existing
  functionality.