[HOTFIX]: Minor clean up regarding skipped artifacts in build files.

There are two relevant 'skip' configurations in the build, the first
is for "mvn install" and the second is for "mvn deploy". As of 1.2,
we actually use "mvn install" to generate our deployed artifcts,
because we have some customization of the nexus upload due to having
to cross compile for Scala 2.10 and 2.11.

There is no reason to have differents settings for these values,
this patch simply cleans this up for the repl/ and yarn/
projects.

Author: Patrick Wendell <patrick@databricks.com>

Closes apache#4080 from pwendell/master and squashes the following commits:

e21b78b [Patrick Wendell] [HOTFIX]: Minor clean up regarding skipped artifacts in build files.

repl/pom.xml

@@ -92,13 +92,6 @@
     <outputDirectory>target/scala-${scala.binary.version}/classes</outputDirectory>
     <testOutputDirectory>target/scala-${scala.binary.version}/test-classes</testOutputDirectory>
     <plugins>
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-deploy-plugin</artifactId>
-        <configuration>
-          <skip>true</skip>
-        </configuration>
-      </plugin>
       <!-- Include a source dir depending on the Scala version -->
       <plugin>
         <groupId>org.codehaus.mojo</groupId>

yarn/pom.xml

@@ -123,16 +123,6 @@
   </profiles>
 
   <build>
-    <plugins>
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-deploy-plugin</artifactId>
-        <configuration>
-          <skip>true</skip>
-        </configuration>
-      </plugin>
-    </plugins>
-
     <outputDirectory>target/scala-${scala.binary.version}/classes</outputDirectory>
     <testOutputDirectory>target/scala-${scala.binary.version}/test-classes</testOutputDirectory>
   </build>