Fix root dependencies from leaking to BOM

Build must be updated to update version for /bom/pom.xml separately.

Change-Id: I0d8fba4a495e7f7bb3f4ed0bee000a9c3ac362f9

bom/pom.xml

@@ -1,14 +1,10 @@
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
-    <parent>
-        <groupId>com.vaadin</groupId>
-        <artifactId>vaadin-root</artifactId>
-        <version>8.0-SNAPSHOT</version>
-    </parent>
     <groupId>com.vaadin</groupId>
     <artifactId>vaadin-bom</artifactId>
     <packaging>pom</packaging>
+    <version>8.0-SNAPSHOT</version>
     <name>Vaadin Framework (Bill of Materials)</name>
     <description>Vaadin Framework (Bill of Materials)</description>
     <url>http://vaadin.com</url>