perf(columns): Reduce calls to moment.js to increase performance

Remove unnecessary calls to moment.js in order to improve performance. Calls to moment.js: startOf, dayOfYear, moment(date) and clone are slow.
perf(timeframes): Do not build time frames if timeFramesMode = hidden

If timeFramesNonWorkingMode/timeFramesWorkingMode is set to hidden then there is no need to build the time frames.
feat(angular): Switch to Angular V1.3.0 for demo and gantt development

Switch to Angular V1.3.0 as it is stable and has a lot of performance improvements
feat(demo): Show how to define a custom header/header-format

Add example of custom header format to show how to control the headers from within the app