Add more dictionaries

ac-dict/c-mode

@@ -0,0 +1,37 @@
+auto
+_Bool
+break
+case
+char
+_Complex
+const
+continue
+default
+do
+double
+else
+enum
+extern
+float
+for
+goto
+if
+_Imaginary
+inline
+int
+long
+register
+restrict
+return
+short
+signed
+sizeof
+static
+struct
+switch
+typedef
+union
+unsigned
+void
+volatile
+while