remove changes files for already-moved things

changes/bug11447

@@ -1,5 +0,0 @@
-  o Minor features (DoS-resistance):
-    - Decrease the amount of reattempts that a hidden service is
-      willing to perform when its rendezvous circuits fail. This
-      reduces the computational cost for hidden service under heavy
-      load. Resolves ticket #11447.

changes/bug15600

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-  o Major bugfixes (security, hidden service):
-    - Fix an issue that would allow a malicious client to trigger
-      an assertion failure and halt a hidden service. Fixes
-      bug 15600; bugfix on 0.2.1.6-alpha. Reported by "skruffy".
-

changes/bug15601

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-  o Major bugfixes (security, hidden service):
-    - Fix a bug that could cause a client to crash with an assertion
-      failure when parsing a malformed hidden service descriptor.
-      Fixes bug 15601; bugfix on 0.2.1.5-alpha. Found by "DonnCha".