DBZ-542 Set protobuf required version to at least 1.2

Author: jpechane

README.md

@@ -17,7 +17,7 @@ A PostgreSQL logical decoder output plugin to deliver data as [Protocol Buffers]
 This code depends on the following libraries and requires them for compilation:
 
 * [PostgreSQL](http://www.postgresql.org) 9.6+
-* [Protobuf-c](https://github.com/protobuf-c/protobuf-c) 1.1+ - used for data serialization
+* [Protobuf-c](https://github.com/protobuf-c/protobuf-c) 1.2+ - used for data serialization
 * [PostGIS](http://www.postgis.net/) 2.1+ - used for Postgres geometric types support
 
 ## Building
@@ -117,4 +117,4 @@ The following table shows how current PostgreSQL type OIDs are mapped to which d
 ## Support
 
 File bug reports and feature requests using [Debezium's JIRA](https://issues.jboss.org/browse/DBZ) and the 
-[postgresql-connector](https://issues.jboss.org/browse/DBZ/component/12323543) component
+[postgresql-connector](https://issues.jboss.org/browse/DBZ/component/12323543) component