Changed 'show solution' button to a 'check' button, to represent the functionality of the button.
Changed icon of check button to check icon.
Changed default value of check button to 'check'.
Changed semantics label and default to correspond with the changes.
Changed enable retry and show solution names.
oppg885
Merge branch 'check-insteadof-showsol' of https://github.com/h5p/h5p-drag-question

Conflicts:
	js/dragquestion.js
Renamed an invalid css class.
Always add buttons and keep them hidden/shown instead.
Revert master. Commited to wrong branch.
Merge branch 'master' of github.com:h5p/h5p-drag-question
Revert "Use number of possible instead of score. This number is the same as score without the minus points."

This reverts commit 1a5f247134bd08d787ae21105d89a0a3c0e41ea9.
Merge branch 'master' into show-score
Merge branch 'show-score'