gitignore: Ignore Kate swap files

(cherry picked from commit e09e0fbd1f45ea51789068115f2dc1d3b93710d7)

.gitignore

@@ -265,9 +265,12 @@ __pycache__/
 # KDE
 .directory
 
-#Kdevelop project files
+# Kdevelop project files
 *.kdev4
 
+# Kate swap files
+*.kate-swp
+
 # Xcode
 xcuserdata/
 *.xcscmblueprint