Moving some stuff

moving base.scss back to library
added a gitignore file to ignore cache files
Base, Header & Single CSS / DOM updates

- changes to base.scss styles (mostly for inputs, selects, textareas,
form elements)
- changes to layout.scss for the header & single product sections
- switched Tech Specs & Social share in Single Product DOM
- minor changes to class naming & additional classes on DOM elements
- edit to searchform.php (for the right arrow in placeholder)