dev-java/jython: Bump guava SLOT, drop readline, EAPI bump

guava:20 is needed so that Java 7 can be dropped from Gentoo.

Support for GNU Readline was dropped from Jython in an earlier version
so the flag and its associated code is of no use now.

There is no need to fix the CLASSPATH in src/shell/jython as this
script is not installed or used at all. I have verified this by
grepping the installed result and deleting the script before building.

Package-Manager: portage-2.3.2

dev-java/jython/files/jython-2.5.2-distutils_scripts_location.patch

@@ -1,5 +1,5 @@
---- Lib/distutils/command/install.py
-+++ Lib/distutils/command/install.py
+--- a/Lib/distutils/command/install.py
++++ b/Lib/distutils/command/install.py
 @@ -70,7 +70,7 @@
          'purelib': '$base/Lib/site-packages',
          'platlib': '$base/Lib/site-packages',

dev-java/jython/files/jython-2.5.2-respect_PYTHONPATH.patch

@@ -1,5 +1,5 @@
---- src/org/python/core/PySystemState.java
-+++ src/org/python/core/PySystemState.java
+--- a/src/org/python/core/PySystemState.java
++++ b/src/org/python/core/PySystemState.java
 @@ -646,6 +646,12 @@
              if (jythonpath != null) {
                  registry.setProperty("python.path", jythonpath);

dev-java/jython/files/jython-2.7.0-build.xml.patch

@@ -1,5 +1,5 @@
---- build.xml.orig	2015-06-27 16:12:08.442000000 +0000
-+++ build.xml	2015-06-27 16:12:15.684000000 +0000
+--- a/build.xml.orig	2015-06-27 16:12:08.442000000 +0000
++++ b/build.xml	2015-06-27 16:12:15.684000000 +0000
 @@ -448,7 +448,7 @@
      </target>