- added feature to sort group exercise list (stored frontend settings on the pc)

...nts/sites/editCustomProjectSite/editCustomProjectSite.tsx

...nts/sites/manageGroupExercisesSite/groupExercisesSite.tsx

src/constants.ts

src/helpers/frontendSettingsManager.ts

...ons/manageGroupExercisesSite/groupExercisesSiteActions.ts

...cers/manageGroupExercisesSite/getGroupExercisesReducer.ts

...ageGroupExercisesSite/getGroupsForExercisesCrudReducer.ts

...manageGroupExercisesSite/groupExercisesSiteActionTypes.ts

...ers/manageGroupExercisesSite/groupExercisesSiteReducer.ts

src/styles/common.styl