delete bootstrap files and create new files

resources/less/bootstrap/mixins/progress-bar.less

resources/less/bootstrap/mixins/reset-filter.less

resources/less/bootstrap/mixins/reset-text.less

resources/less/bootstrap/mixins/resize.less

resources/less/bootstrap/mixins/responsive-visibility.less

resources/less/bootstrap/mixins/size.less

resources/less/bootstrap/mixins/table-row.less

resources/less/bootstrap/mixins/text-overflow.less

resources/less/bootstrap/mixins/vendor-prefixes.less

resources/less/metager/mixins/clearfix.less

resources/less/metager/mixins/forms.less

resources/less/metager/mixins/grid.less

resources/less/metager/mixins/mixins.less

resources/less/metager/mixins/tab-focus.less

resources/less/metager/mixins/text-emphasis.less

resources/less/metager/mixins/vendor-prefixes.less