Atom - hide file icons and replace arrows

styles.less

.tree-view {
    .icon:before {
        display:none;
    }
    .list-group li:not(.list-nested-item), .list-tree li:not(.list-nested-item), .list-group li.list-nested-item > .list-item, .list-tree li.list-nested-item > .list-item {
        line-height: 21px;
    }
    .list-group .selected:before, .list-tree .selected:before {
        height: 21px;
    }
    &.list-tree.has-collapsable-children .list-nested-item {
        > .list-item:before{
            content: "\f05b";
            opacity: 0.25;
        }
        &.collapsed > .list-item:before{
            content: "\f05a";
            opacity: 0.25;
        }
        > .list-tree > li {
            padding-left: 10px;
        }
    }
}