releases: fix typo and update format in 1.1 Alpha (#447)

releases/11alpha.md

@@ -15,11 +15,11 @@ On January 19, 2018, TiDB 1.1 Alpha is released. This release has great improvem
     - Use more compact structure to reduce statistics info memory usage
     - Speed up loading statistics info when starting tidb-server
     - Provide more accurate query cost evaluation
-    - Use Count-Min Sketch to evaluate the cost of queries using unique index more accurately
+    - Use `Count-Min Sketch` to estimate the cost of queries using unique index more accurately
     - Support more complex conditions to make full use of index
 - SQL executor
     - Refactor all executor operators using Chunk architecture, improve the execution performance of analytical statements and reduce memory usage
-    - Optimize performance of the `INSERT INGORE` statement
+    - Optimize performance of the `INSERT IGNORE` statement
     - Push down more types and functions to TiKV
     - Support more `SQL_MODE`
     - Optimize the `Load Data` performance to increase the speed by 10 times
@@ -39,14 +39,14 @@ On January 19, 2018, TiDB 1.1 Alpha is released. This release has great improvem
 ## TiKV:
 
 - Support Raft learner
-- Optimize Raft Snapshot and reduce the IO overhead
+- Optimize Raft Snapshot and reduce the I/O overhead
 - Support TLS
 - Optimize the RocksDB configuration to improve performance
 - Optimize `count (*)` and query performance of unique index in Coprocessor
 - Add more failpoints and stability test cases
 - Solve the reconnection issue between PD and TiKV
-- Enhance the features of the data recovery tool TiKV-CTL
+- Enhance the features of the data recovery tool `tikv-ctl`
 - Support splitting according to table in Region
 - Support the `Delete Range` feature
-- Support setting the IO limit caused by snapshot
+- Support setting the I/O limit caused by snapshot
 - Improve the flow control mechanism