make Guava version configurable at build time
<logback.version>1.1.0</logback.version>
<h2.version>1.4.194</h2.version>
<tika.version>1.17</tika.version>
+ <guava.version>15.0</guava.version>
<findbugs.version>3.0.4</findbugs.version>
<derby.version>10.14.1.0</derby.version>
<java.version>1.8</java.version>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
- <version>15.0</version>
+ <version>${guava.version}</version>
</dependency>
<dependency>
<groupId>org.easymock</groupId>
