Update gitignore and settings.json (#582)

* Ignore tmp files in gitignore

* Update .vscode/settings.json

.gitignore

@@ -94,3 +94,4 @@ Temporary Items
 coverage.info
 /coverage
 
+*.tmp

.vscode/settings.json

@@ -5,6 +5,11 @@
         "__locale": "c",
         "string": "c",
         "string_view": "c",
-        "vector": "c"
+        "vector": "c",
+        "jpegcodec.h": "c",
+        "jpeglib.h": "c",
+        "dstream.h": "c",
+        "jconfig.h": "c",
+        "jmorecfg.h": "c"
     }
 }