Edit README to refer to 1.6.12 release and 1.6.13-SNAPSHOT.

Author: jxblum

README.adoc

@@ -77,8 +77,8 @@ The following SBDG versions are currently maintained and developed.
 | `2.0.0-M4`| https://docs.spring.io/spring-boot-data-geode-build/2.0.x/reference/html5/[Ref Docs] | https://docs.spring.io/spring-boot-data-geode-build/2.0.x/api/[Javadoc] | https://docs.spring.io/spring-boot-data-geode-build/2.0.x/reference/html5/#geode-samples[Samples]
 | `1.7.4-SNAPSHOT`| https://docs.spring.io/spring-boot-data-geode-build/1.7.x-SNAPSHOT/reference/html5/[Ref Docs] | https://docs.spring.io/spring-boot-data-geode-build/1.7.x-SNAPSHOT/api/[Javadoc] | https://docs.spring.io/spring-boot-data-geode-build/1.7.x-SNAPSHOT/reference/html5/#geode-samples[Samples]
 | `1.7.3`| https://docs.spring.io/spring-boot-data-geode-build/1.7.x/reference/html5/[Ref Docs] | https://docs.spring.io/spring-boot-data-geode-build/1.7.x/api/[Javadoc] | https://docs.spring.io/spring-boot-data-geode-build/1.7.x/reference/html5/#geode-samples[Samples]
-| `1.6.12-SNAPSHOT`| https://docs.spring.io/spring-boot-data-geode-build/1.6.x-SNAPSHOT/reference/html5/[Ref Docs] | https://docs.spring.io/spring-boot-data-geode-build/1.6.x-SNAPSHOT/api/[Javadoc] | https://docs.spring.io/spring-boot-data-geode-build/1.6.x-SNAPSHOT/reference/html5/#geode-samples[Samples]
-| `1.6.11`| https://docs.spring.io/spring-boot-data-geode-build/1.6.x/reference/html5/[Ref Docs] | https://docs.spring.io/spring-boot-data-geode-build/1.6.x/api/[Javadoc] | https://docs.spring.io/spring-boot-data-geode-build/1.6.x/reference/html5/#geode-samples[Samples]
+| `1.6.13-SNAPSHOT`| https://docs.spring.io/spring-boot-data-geode-build/1.6.x-SNAPSHOT/reference/html5/[Ref Docs] | https://docs.spring.io/spring-boot-data-geode-build/1.6.x-SNAPSHOT/api/[Javadoc] | https://docs.spring.io/spring-boot-data-geode-build/1.6.x-SNAPSHOT/reference/html5/#geode-samples[Samples]
+| `1.6.12`| https://docs.spring.io/spring-boot-data-geode-build/1.6.x/reference/html5/[Ref Docs] | https://docs.spring.io/spring-boot-data-geode-build/1.6.x/api/[Javadoc] | https://docs.spring.io/spring-boot-data-geode-build/1.6.x/reference/html5/#geode-samples[Samples]
 
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