add options for grading all submissions of a specific problem (grafted from branch algo-bm 8ed1c0aa59eaf8e22e40fc765c1fba4ac88a34b5)

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extra : source : 8ed1c0aa59eaf8e22e40fc765c1fba4ac88a34b5
Merge pull request #6 from nattee/master

add options for grading all submissions of a specific problem