Fix lots of spelling errors (#7751)

* Fix a typo

* Fix lots of spelling errors

* Fix a few more spelling mistakes

* s/parsable/parseable/

* Don't touch the third party files

* Cloneable is the preferred C# term

* Copyable is the preferred C++ term

* Revert "s/parsable/parseable/"

This reverts commit 534ecf7675222f39d98928c7e1489b56b004b774.

* Revert unparseable->unparsable corrections
diff --git a/docs/implementing_proto3_presence.md b/docs/implementing_proto3_presence.md
index fae2eb5..73f21a3 100644
--- a/docs/implementing_proto3_presence.md
+++ b/docs/implementing_proto3_presence.md
@@ -13,7 +13,7 @@
 updated already. However third-party code generators will need to be updated
 independently by their authors. This includes:
 
-- implementations of Protocol Buffers for other languges.
+- implementations of Protocol Buffers for other languages.
 - alternate implementations of Protocol Buffers that target specialized use
   cases.
 - RPC code generators that create generated APIs for service calls.