[clang] [clang-repl] adding documentation and information for %commands (PR #150348)

[David Spickett via cfe-commits]

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@@ -347,7 +348,15 @@ int main(int argc, const char **argv) {
     }
   }
 
+  // if we add more % commands, there should be better architecture than this
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DavidSpickett wrote:

Format your comments as if they were normal written sentences. Which means capital letter start and period end.

Generally. If it's super short then sure, do whatever. But if it feels like a sentence, make it a proper one.

https://github.com/llvm/llvm-project/pull/150348