Refactor the Scss functions library

- Improve get-layout-direction function
- Remove replace-nth function
Improve code quality
Prefix every function with 'jeet-' for namespacing
Add a fallback for Sass 3.2 for 'set-nth()' function
Move $width to config for easier settings modification
Make all settings variables default values so they can be easily overidden
Improve code quality
Add a 3.3 enhanced version of the 'jeet-reverse()' function
Rename some function arguments for clarity
Remove jeet.gutter alias as it's not used
Move default styles above conditionals
Improve code formatting consistancy
Impove code formatting

- Bring it in line with Scss
- Made a few structural changes for the sake of consistancy with Scss
Fix incorrect variable name in documentation
Add JSDoc style documentation to all functions and mixins

- Replace instances of 'g' with 'gutter'
- Clean up the code formatting a bit too
Add more verbose documentaion for settings files
Add jeet.max-width varaible to settings page for easy modification