Provide incremental compilation for Maven

#KT-11916 fixed

To use the IC either:
1. set the `kotlin.compiler.incremental` property to `true` in a pom.xml:
```
<properties>
    <kotlin.compiler.incremental>true</kotlin.compiler.incremental>
</properties>
```
2. pass the `kotlin.compiler.incremental` property in a command line:
```
mvn install -Dkotlin.compiler.incremental=true
```

When IC is on Kotlin plugin is expected to print the warning in the log:
```
Using experimental Kotlin incremental compilation
```

After each call an incremental compiler will also log how many files it has compiled:
```
Compiled %SOME_NUMBER% Kotlin files using incremental compiler
```

Note that the first build will be non-incremental.

For more diagnostic information (such as an exact list of compiled files) use the `kotlin.compiler.incremental.log.level` system property:
```
mvn install -Dkotlin.compiler.incremental=true -Dkotlin.compiler.incremental.log.level=info
```

To force the rebuild just run the 'clean' goal:
```
mvn clean install
```

libraries/tools/kotlin-maven-plugin-test/pom.xml

@@ -12,8 +12,45 @@
 
     <artifactId>kotlin-maven-plugin-test</artifactId>
 
+    <dependencies>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.12</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.jetbrains.kotlin</groupId>
+            <artifactId>kotlin-maven-plugin</artifactId>
+            <version>${project.version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
     <build>
+        <testSourceDirectory>${project.basedir}/src/test/java</testSourceDirectory>
+
+        <resources>
+            <resource>
+                <directory>${project.basedir}/src/test/resources</directory>
+                <filtering>true</filtering>
+            </resource>
+        </resources>
+
         <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+
+                <executions>
+                    <execution>
+                        <id>test-compile</id>
+                        <phase>test-compile</phase>
+                        <goals><goal>testCompile</goal></goals>
+                    </execution>
+                </executions>
+            </plugin>
+
             <plugin>
                 <artifactId>maven-deploy-plugin</artifactId>
                 <configuration>
@@ -35,6 +72,33 @@
             </activation>
             <build>
                 <plugins>
+                    <plugin>
+                        <artifactId>maven-failsafe-plugin</artifactId>
+                        <version>2.6</version>
+                        <executions>
+                            <execution>
+                                <goals>
+                                    <goal>integration-test</goal>
+                                    <goal>verify</goal>
+                                </goals>
+                                <configuration>
+                                    <jvm>${env.JAVA_HOME}/bin/java</jvm>
+                                    <forkMode>once</forkMode>
+                                    <systemProperties>
+                                        <property>
+                                            <name>maven.home</name>
+                                            <value>${maven.home}</value>
+                                        </property>
+                                        <property>
+                                            <name>kotlin.version</name>
+                                            <value>${project.version}</value>
+                                        </property>
+                                    </systemProperties>
+                                </configuration>
+                            </execution>
+                        </executions>
+                    </plugin>
+
                     <plugin>
                         <artifactId>maven-invoker-plugin</artifactId>
                         <version>1.9</version>