chore: rework update-translations.sh into pom file as a profile

Closes #479

README.md

@@ -79,6 +79,10 @@ In order to build the source code for PgJDBC you will need the following tools:
 - A JDK for the JDBC version you'd like to build (JDK6 for JDBC 4, JDK7 for JDBC 4.1 or JDK8 for JDBC 4.2)
 - A running PostgreSQL instance
 
+Additionally, in order to update translations (not typical), you will need the following additional tools:
+
+-  the gettext package, which contains the commands "msgfmt", "msgmerge", and "xgettext"
+
 ## Checking out the source code
 
 The PgJDBC project uses git for version control. You can check out the current code by running:
@@ -162,6 +166,19 @@ Here's sample configuration for Mac OS:
 </toolchains>
 ```
 
+## Updating translations
+
+From time to time, the translation packages will need to be updated as part of the build process.
+However, this is atypical, and is generally only done when needed such as by a project committer before a major release.
+This process adds additional compile time and generally should not be executed for every build.
+
+Updating translations can be accomplished with the following command:
+
+    mvn -Ptranslate compile && git add pgjdbc && git commit -m "Translations updated"
+
+Note that the maven profile "translate" can safely be called with other profiles, such as -P release-artifacts.
+Invocation of this command will generate new .po files, a new messages.pot file, and newly translated class files.
+
 ## Releasing a snapshot version
 
 TravisCI automatically deploys snapshots for each commit to master branch.

pgjdbc/pom.xml

@@ -37,6 +37,86 @@
     <skip.assembly>false</skip.assembly>
   </properties>
 
+  <profiles>
+    <profile>
+      <id>translate</id>
+      <activation>
+        <activeByDefault>false</activeByDefault>
+      </activation>
+      <build>
+        <plugins>
+          <plugin>
+            <groupId>com.googlecode.gettext-commons</groupId>
+            <artifactId>gettext-maven-plugin</artifactId>
+            <version>1.2.4</version>
+            <executions>
+              <execution>
+                <id>generate_pot_and_po_files</id>
+                <phase>generate-resources</phase>
+                <goals>
+                  <goal>merge</goal>
+                </goals>
+                <configuration>
+                  <outputDirectory>src/main/resources</outputDirectory>
+                </configuration>
+              </execution>
+              <execution>
+                <id>generate_resource_bundles</id>
+                <phase>generate-resources</phase>
+                <goals>
+                  <goal>dist</goal>
+                </goals>
+              </execution>
+            </executions>
+            <configuration>
+              <sourceDirectory>${project.build.sourceDirectory}</sourceDirectory>
+              <outputDirectory>src/main/resources</outputDirectory>
+              <keysFile>messages.pot</keysFile>
+              <poDirectory>src/main/java/org/postgresql/translation</poDirectory>
+              <targetBundle>org.postgresql.translation.messages</targetBundle>
+              <keywords>-kGT.tr</keywords>
+              <msgmergeCmd>msgmerge</msgmergeCmd>
+            </configuration>
+          </plugin>
+          <plugin>
+            <artifactId>maven-clean-plugin</artifactId>
+            <executions>
+              <execution>
+                <id>clean_msmerge_backups</id>
+                <goals>
+                  <goal>clean</goal>
+                </goals>
+                <phase>compile</phase>
+                <configuration>
+                  <!-- Do not delete target folder -->
+                  <excludeDefaultDirectories>true</excludeDefaultDirectories>
+                  <filesets>
+                    <fileset>
+                      <directory>src/main/resources/org/postgresql/translation</directory>
+                      <includes>
+                        <include>**$*.class</include>
+                        <include>messages.properties</include>
+                        <include>messages_en.properties</include>
+                      </includes>
+                      <followSymlinks>false</followSymlinks>
+                    </fileset>
+                    <fileset>
+                      <directory>src/main/java/org/postgresql/translation</directory>
+                      <includes>
+                        <include>*.po.~*~</include>
+                      </includes>
+                      <followSymlinks>false</followSymlinks>
+                    </fileset>
+                  </filesets>
+                </configuration>
+              </execution>
+            </executions>
+          </plugin>
+        </plugins>
+      </build>
+    </profile>
+  </profiles>
+
   <build>
     <plugins>
       <plugin>