Prepare version 3.0.0-alpha2.

Author: greenrobot-team

build.gradle

@@ -5,7 +5,7 @@ buildscript {
     ext {
         // Typically, only edit those two:
         def objectboxVersionNumber = '3.0.0-alpha2' // without "-SNAPSHOT", e.g. '2.5.0' or '2.4.0-RC'
-        def objectboxVersionRelease = false  // set to true for releasing to ignore versionPostFix to avoid e.g. "-dev" versions
+        def objectboxVersionRelease = true  // set to true for releasing to ignore versionPostFix to avoid e.g. "-dev" versions
 
         // version post fix: '-<value>' or '' if not defined; e.g. used by CI to pass in branch name
 //        def versionPostFixValue = project.findProperty('versionPostFix')