update eclipse projects (partest, repl & scaladoc)

Since we've removed scala.annotations.serializable in 2.11,
you'll need to following bandaid to use eclipse on master.

This is the easiest fix, but certainly not recommended in general.

```
--- i/src/eclipse/scala-library/.classpath
+++ w/src/eclipse/scala-library/.classpath
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
        <classpathentry kind="src" path="library"/>
-       <classpathentry kind="con" path="org.scala-ide.sdt.launching.SCALA_CONTAINER"/>
+       <classpathentry exported="true" kind="con" path="org.scala-ide.sdt.launching.SCALA_CONTAINER"/>
```

This corresponds to checking the export check box for the scala library jar
in the library's build path.