fix changelog

CHANGELOG.md

@@ -7,6 +7,7 @@ Please mark all change in change log and use the ticket from JIRA.
 - \#228 - memory usage increased slowly during searching vectors
 - \#246 - Exclude src/external folder from code coverage for jenkin ci
 - \#248 - Reside src/external in thirdparty
+- \#316 - Some files not merged after vectors added
 
 ## Feature
 - \#12 - Pure CPU version for Milvus
@@ -20,6 +21,7 @@ Please mark all change in change log and use the ticket from JIRA.
 - \#260 - C++ SDK README
 - \#314 - add Find FAISS in CMake
 - \#310 - Add Q&A for 'protocol https not supported or disable in libcurl' issue
+- \#322 - Add option to enable / disable prometheus
 
 ## Task