Bug 400517 - [CBI] version qualifiers can be "after" build ID

use buildTimestamp
diff --git a/platform/org.eclipse.platform/pom.xml b/platform/org.eclipse.platform/pom.xml
index 55c14ab..5400275 100644
--- a/platform/org.eclipse.platform/pom.xml
+++ b/platform/org.eclipse.platform/pom.xml
@@ -31,7 +31,7 @@
         <artifactId>tycho-packaging-plugin</artifactId>
         <version>${tycho.version}</version>
         <configuration>
-          <format>'v${maven.build.timestamp}'</format>
+          <format>'v${buildTimestamp}'</format>
         </configuration>
       </plugin>
     </plugins>
diff --git a/platform/org.eclipse.sdk/pom.xml b/platform/org.eclipse.sdk/pom.xml
index 4a24ff2..690b30e 100644
--- a/platform/org.eclipse.sdk/pom.xml
+++ b/platform/org.eclipse.sdk/pom.xml
@@ -31,7 +31,7 @@
         <artifactId>tycho-packaging-plugin</artifactId>
         <version>${tycho.version}</version>
         <configuration>
-          <format>'v${maven.build.timestamp}'</format>
+          <format>'v${buildTimestamp}'</format>
         </configuration>
       </plugin>
     </plugins>