Move folder: src/core/utils/ → src/utils/

[Raruto]

Preparatory for: #505

List of changes

• move whole files in folder: src/core/utils/*.js → src/utils/*.js
• extract some functions into single files: src/core/utils/utils.js → src/utils/*.js
• remove unusued module: utils/ol.controls'

Before

const utils    = require('core/utils/utils');
const geoutils = require('core/utils/geo');
const parsers  = require('core/utils/parsers');

After

const utils    = require('utils');
const geoutils = require('utils/geo');
const parsers  = require('utils/parsers');