feat(BOM): publish a complete runtime BOM file (#349)

in order for Studio to freeze all runtime dependencies to
the versions the runtime pull (directly or transitively)

Relates to [RUNTIME-296](https://bonitasoft.atlassian.net/browse/RUNTIME-296)

bonita-runtime-bom/pom.xml

+<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/maven-v4_0_0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>org.bonitasoft.runtime</groupId>
+    <artifactId>bonita-runtime-bom</artifactId>
+    <version>7.13.0-SNAPSHOT</version>
+
+    <name>Bonita Runtime BOM (Bill of Materials)</name>
+    <packaging>pom</packaging>
+
+    <dependencyManagement>
+        <dependencies>
+            <dependency>
+                <groupId>org.bonitasoft.engine</groupId>
+                <artifactId>bonita-engine</artifactId>
+                <version>${project.version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+            <dependency>
+                <groupId>org.bonitasoft.console</groupId>
+                <artifactId>bonita-web-bom</artifactId>
+                <version>${project.version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+            <dependency>
+                <groupId>javax.servlet</groupId>
+                <artifactId>javax.servlet-api</artifactId>
+                <version>3.1.0</version>
+            </dependency>
+        </dependencies>
+    </dependencyManagement>
+
+</project>
\ No newline at end of file

pom.xml

@@ -8,6 +8,7 @@
     <packaging>pom</packaging>
 
     <modules>
+        <module>bonita-runtime-bom</module>
         <module>resources</module>
         <module>bonita-war</module>
         <module>tomcat-resources</module>