Fix Javadoc generation for lombok classes (#901)

Move lombok classes to a separate directory and configure
a Maven plugin to put 'delomboked' classes in 'target/generated-sources'
so that the Javadoc tool can operate on the Lombok-enhanced
Java _source_ files.

Author: bullet-tooth

exonum-light-client/pom.xml

@@ -270,6 +270,20 @@
           </execution>
         </executions>
       </plugin>
+
+      <plugin>
+        <groupId>org.projectlombok</groupId>
+        <artifactId>lombok-maven-plugin</artifactId>
+        <version>1.18.6.0</version>
+        <executions>
+          <execution>
+            <phase>generate-sources</phase>
+            <goals>
+              <goal>delombok</goal>
+            </goals>
+          </execution>
+        </executions>
+      </plugin>
     </plugins>
   </build>
 
@@ -291,6 +305,20 @@
             <groupId>org.jacoco</groupId>
             <artifactId>jacoco-maven-plugin</artifactId>
             <version>0.8.3</version>
+            <configuration>
+              <excludes>
+                <!--
+                Exclude lombok annotated classes which are located at `src/main/lombok`,
+                because the plugin can't be configured to look for sources there.
+                -->
+                <exclude>com/exonum/client/response/Block.class</exclude>
+                <exclude>com/exonum/client/response/Block*BlockBuilder.class</exclude>
+                <exclude>com/exonum/client/response/BlockResponse.class</exclude>
+                <exclude>com/exonum/client/response/BlocksResponse.class</exclude>
+                <exclude>com/exonum/client/response/HealthCheckInfo.class</exclude>
+                <exclude>com/exonum/client/response/TransactionResponse.class</exclude>
+              </excludes>
+            </configuration>
             <executions>
               <execution>
                 <id>prepare-jacoco-agent</id>

exonum-light-client/src/main/java/com/exonum/client/response/Block.java renamed to exonum-light-client/src/main/lombok/com/exonum/client/response/Block.java

@@ -43,7 +43,7 @@ public class Block {
   int proposerId;
 
   /**
-   * Returns the height of this block which is a distance between the last block and the "genesis"
+   * The height of this block which is a distance between the last block and the "genesis"
    * block. Genesis block has 0 height. Therefore, the blockchain height is equal to
    * the number of blocks plus one.
    *

exonum-light-client/src/main/java/com/exonum/client/response/BlockResponse.java renamed to exonum-light-client/src/main/lombok/com/exonum/client/response/BlockResponse.java

@@ -22,8 +22,8 @@
 @Value
 public class HealthCheckInfo {
   /**
-   * Shows information about whether it is possible to achieve the consensus between
-   * validators in the current state.
+   * Consensus status shows/indicates whether it is possible
+   * to achieve the consensus between validators in the current network state.
    */
   ConsensusStatus consensusStatus;