Website changed to new flow

Changes to root:
- index.html changed to use new flow
- answer.html opens a question+answer from email
- thanks.html shows a thank you for your question message

Changes to css:
- CSS Lint fixes
- Added CSS for new buttons and textfields (in answers.html)

Changes to js folder:
- fancyshowhide.js doesn't use a timer.
- feedbackanswer.js sends feedback to server (NOT FULLY TESTED, Error on
backend!)
- onClick.js added handlers for new buttons
- showhide.js added functionality for showing and hiding the "Not my
answer" button in index.html
- submitforms.js submits new validated question to server, removed
checkAnswer function, because of website flow changes
- validationforms.js minor changes to validate correct input for the
server
- answerOnload.js function that handles translation for answer.html and
retrieves question + answer from server
- getAnswer.js retrieves answer and question from server
- getSimilarQuestion.js retrieves multiple answers and questions from
server to show immediately when a user creates a new question
- navigateToIndex.js function to ask a new question
- retrieveGetValues.js gets the feedbacktoken from url
- translate-xxx.js functions to translate the website to dutch or
english
- translations folder contains .csv files with translated strings for
website in dutch and english

Changes to test folder:
- removed showhide test, because it couldn't be implemented as first
thought
- added getAnswerTest.js, but this isn't finished because I don't have
any valid feedbacktokens (NOT IMPLEMENTED, Error on backend!).