Update version to 4.5

Summary: Time to cut branch for release 4.5. Change the versions.

Test Plan: Not needed

Reviewers: IslamAbdelRahman, yhchiang, kradhakrishnan, andrewkr, anthony

Reviewed By: anthony

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D53883

HISTORY.md

@@ -1,5 +1,7 @@
 # Rocksdb Change Log
 ## Unreleased
+
+## 4.5.0 (2/5/2016)
 ### Public API Changes
 * Add a new perf context level between kEnableCount and kEnableTime. Level 2 now doesn't include timers for mutexes.
 * Statistics of mutex operation durations will not be measured by default. If you want to have them enabled, you need to set Statistics::stats_level_ to kAll.

include/rocksdb/version.h

@@ -5,7 +5,7 @@
 #pragma once
 
 #define ROCKSDB_MAJOR 4
-#define ROCKSDB_MINOR 4
+#define ROCKSDB_MINOR 5
 #define ROCKSDB_PATCH 0
 
 // Do not use these. We made the mistake of declaring macros starting with