Starklings Add Exercice functionnality

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Add the exercice page to the Starklings web version.

• Add text editor
• Add Instructions
• Add Documentation link
• Call back-end for result After succeed move to the next exercice automatically

[sxxnx]

UPDATE

• Using Monaco Editor as an Editor
• Need to get the syntax config myself because Cairo is not supported yet

[sxxnx]

• Fetching exercices from github directly
• find a way to extract the instructions of the exercices
• The code displayed in editor should be edited so that it does not display the instructions
• The instructions are displayed on the left part of the editor div.instruction

[sxxnx]

Since the development of Cairo language support for Monaco editor may take a long time we agreed to the following changes for the moment :

• Upload cairo file button = user uploads the exercice and get success or fail response
• Upload the text of the cairo file into the editor and get success or fail response