renamed sidebar entry `Fixed` to `Fixed Sidebar` & renamed file `fixed.html` to `fixed-sidebar.html`

- added .anchor for anchors with offset while fixed navbar
- fixed .main-header border
- added sidebar color variations (colors)
- added pre & blockquote style for doc usage
- fixed brand-link width with .logo-switch

more changes to release v3.0.0-beta.2

 Updating devDependencies for "js" script.

This reverts commit 03ed07ba.

- removed js margin-top/-bottom generation
- added layout-navbar-not-fixed & layout-footer-not-fixed incl. responsive variants (eg. layout-*-navbar-not-fixed, layout-*-footer-not-fixed)
- added responsive variants for fixed (eg. layout-*-navbar-fixed, layout-*-footer-fixed)
- added default border-bottom to main-header navbar like main-footer
- removed .border-bottom from main-header navbar in demo pages

Change "js-compile" script. Moving settings files to one place.

Bootstarap 3 > 4

- added display none/block to control-sidebar to avoid sidewards scrolling
- reworked ControlSidebar.js with queue to add and remove .control-sidebar-animate from html to avoid overflow

Edit bootstarap 3 > 4

Package.json -> scripts. Module "cleancss"

further steps to beta.2

- updated DataTables typo in demo files
- added jsGrid to package,json & npm/Plugins.js
- added jsgrid demo

- created project_add & project_edit
- updated project_detail
- added menu link to all demo files
- added a line break in _colors.scss

- added !important to elevation-* & text-sm, text-xs, text-lg & text-xl
- added variables for ribbon
- added ribbon style code in scss/_miscellaneous