Show current files filter as radio buttons

I renamed the "Reset filter" item to "No filter" to make it look more like a
state than an action, so that it fits the radio button concept better.

When there are conflicts and we set the filter to show only conflicting files,
then none of the radio buttons light up, which is slightly strange. I guess it's
ok though.

pkg/gui/controllers/files_controller.go

@@ -753,6 +753,7 @@ func (self *FilesController) isResolvingConflicts() bool {
 }
 
 func (self *FilesController) handleStatusFilterPressed() error {
+	currentFilter := self.context().GetFilter()
 	return self.c.Menu(types.CreateMenuOptions{
 		Title: self.c.Tr.FilteringMenuTitle,
 		Items: []*types.MenuItem{
@@ -761,35 +762,40 @@ func (self *FilesController) handleStatusFilterPressed() error {
 				OnPress: func() error {
 					return self.setStatusFiltering(filetree.DisplayStaged)
 				},
-				Key: 's',
+				Key:    's',
+				Widget: types.MakeMenuRadioButton(currentFilter == filetree.DisplayStaged),
 			},
 			{
 				Label: self.c.Tr.FilterUnstagedFiles,
 				OnPress: func() error {
 					return self.setStatusFiltering(filetree.DisplayUnstaged)
 				},
-				Key: 'u',
+				Key:    'u',
+				Widget: types.MakeMenuRadioButton(currentFilter == filetree.DisplayUnstaged),
 			},
 			{
 				Label: self.c.Tr.FilterTrackedFiles,
 				OnPress: func() error {
 					return self.setStatusFiltering(filetree.DisplayTracked)
 				},
-				Key: 't',
+				Key:    't',
+				Widget: types.MakeMenuRadioButton(currentFilter == filetree.DisplayTracked),
 			},
 			{
 				Label: self.c.Tr.FilterUntrackedFiles,
 				OnPress: func() error {
 					return self.setStatusFiltering(filetree.DisplayUntracked)
 				},
-				Key: 'T',
+				Key:    'T',
+				Widget: types.MakeMenuRadioButton(currentFilter == filetree.DisplayUntracked),
 			},
 			{
-				Label: self.c.Tr.ResetFilter,
+				Label: self.c.Tr.NoFilter,
 				OnPress: func() error {
 					return self.setStatusFiltering(filetree.DisplayAll)
 				},
-				Key: 'r',
+				Key:    'r',
+				Widget: types.MakeMenuRadioButton(currentFilter == filetree.DisplayAll),
 			},
 		},
 	})

pkg/i18n/english.go

@@ -89,7 +89,7 @@ type TranslationSet struct {
 	FilterUnstagedFiles                   string
 	FilterTrackedFiles                    string
 	FilterUntrackedFiles                  string
-	ResetFilter                           string
+	NoFilter                              string
 	MergeConflictsTitle                   string
 	Checkout                              string
 	CheckoutTooltip                       string
@@ -1115,7 +1115,7 @@ func EnglishTranslationSet() *TranslationSet {
 		FilterUnstagedFiles:                  "Show only unstaged files",
 		FilterTrackedFiles:                   "Show only tracked files",
 		FilterUntrackedFiles:                 "Show only untracked files",
-		ResetFilter:                          "Reset filter",
+		NoFilter:                             "No filter",
 		NoChangedFiles:                       "No changed files",
 		SoftReset:                            "Soft reset",
 		AlreadyCheckedOutBranch:              "You have already checked out this branch",

pkg/integration/tests/conflicts/filter.go

@@ -25,7 +25,7 @@ var Filter = NewIntegrationTest(NewIntegrationTestArgs{
 			Tap(func() {
 				t.ExpectPopup().Menu().
 					Title(Equals("Filtering")).
-					Select(Contains("Reset filter")).
+					Select(Contains("No filter")).
 					Confirm()
 			}).
 			Lines(

pkg/integration/tests/filter_and_search/filter_by_file_status.go

@@ -52,7 +52,7 @@ var FilterByFileStatus = NewIntegrationTest(NewIntegrationTestArgs{
 			Tap(func() {
 				t.ExpectPopup().Menu().
 					Title(Equals("Filtering")).
-					Select(Contains("Reset filter")).
+					Select(Contains("No filter")).
 					Confirm()
 			}).
 			Lines(