Added template.html and necessary dependencies

changed website's charset to utf-8 in order to keep eclipse from complaining

created basic structure necessary for the sticky footer

- main.css renamed to main.less
- support for LESS, a dynamic stylesheet language, added with less-1.3.3.min.js
- LESS included in header of main.html

created folder structure of html files:
--- views/
------ errors/
--------- 404.html
--------- 500.html
------ pages/
--------- YOUR OWN HTML
------ tags/
--------- advertisement.html
--------- navigationBarAuth.html
--------- navigationBarNoAuth.html
------ template.html

renamed main.less to template.less

- Controller: MainPage.java created, which takes care of the (not) authenticated main page
- Page: mainPageNotAuth.html created with some short code to get it displayed
- footer added to template.html
- Routes: / opens MainPage.java
- CSS: old stylesheet code copied into template.less; this has to be edited for the new html code

footer and basic navigation bar created

- template with if condition for (not) authenticated navigation bar
- created necessary tags for the (not) authenticated navigation bar

updated jquery.js, imported jquery-ui.js and navigationBarPopUp.js; these are necessary for the popup menu in the navigation bar

cleaned up header of template.html

- navigationBarAuth.html and navigationBarNotAuth.html is not finished yet
- template.html is stable
- navigationBarPopUp.js and navigationBarPopUp.less is not finished yet