Use sentence case everywhere

We have not been good at consistent casing so far. Now we use 'Sentence case' everywhere. EVERYWHERE.

Also Removing 'Lc' prefix from i18n field names: the 'Lc' stood for lowercase but now that everything
is in 'Sentence case' there's no need for the distinction.

I've got a couple lower case things I've kept: namely, things that show up in parentheses.

pkg/integration/tests/reflog/checkout.go

@@ -29,7 +29,7 @@ var Checkout = NewIntegrationTest(NewIntegrationTestArgs{
 			PressPrimaryAction().
 			Tap(func() {
 				t.ExpectPopup().Confirmation().
-					Title(Contains("checkout commit")).
+					Title(Contains("Checkout commit")).
 					Content(Contains("Are you sure you want to checkout this commit?")).
 					Confirm()
 			}).

pkg/integration/tests/reflog/cherry_pick.go

@@ -38,7 +38,7 @@ var CherryPick = NewIntegrationTest(NewIntegrationTestArgs{
 			Press(keys.Commits.PasteCommits).
 			Tap(func() {
 				t.ExpectPopup().Alert().
-					Title(Equals("Cherry-Pick")).
+					Title(Equals("Cherry-pick")).
 					Content(Contains("Are you sure you want to cherry-pick the copied commits onto this branch?")).
 					Confirm()
 			}).

pkg/integration/tests/reflog/patch.go

@@ -47,15 +47,15 @@ var Patch = NewIntegrationTest(NewIntegrationTestArgs{
 			).
 			PressPrimaryAction()
 
-		t.Views().Information().Content(Contains("building patch"))
+		t.Views().Information().Content(Contains("Building patch"))
 
 		t.Views().
 			CommitFiles().
 			Press(keys.Universal.CreatePatchOptionsMenu)
 
 		t.ExpectPopup().Menu().
-			Title(Equals("Patch Options")).
-			Select(MatchesRegexp(`apply patch$`)).Confirm()
+			Title(Equals("Patch options")).
+			Select(MatchesRegexp(`Apply patch$`)).Confirm()
 
 		t.Views().Files().Lines(
 			Contains("file1"),

pkg/integration/tests/reflog/reset.go

@@ -29,8 +29,8 @@ var Reset = NewIntegrationTest(NewIntegrationTestArgs{
 			Press(keys.Commits.ViewResetOptions).
 			Tap(func() {
 				t.ExpectPopup().Menu().
-					Title(Contains("reset to")).
-					Select(Contains("hard reset")).
+					Title(Contains("Reset to")).
+					Select(Contains("Hard reset")).
 					Confirm()
 			}).
 			TopLines(