#21 Migration to Java7

[Till Schäfer]

For now the Sourcecode still uses the Java6 types and libraries and we are also compiling the releases with Java6. Sine Java6 runs out of maintenance we should prepare our code for Java7.

To be not misunderstood: The current releases can be run without problems under Java7 and the issues we had at the beginning with CDK (which causes exceptions while sorting with timsort) are resolved.

However, when using a Java7 compiler, we have a lot of warnings about raw types in the swing libraries. They are now generics and we should make use of them. We can still compile the code with java7 for java6 runtime compatibility, when we are changing this now. Maybe the ant build.xml must be adjusted to use this compatibility.

[Till Schäfer]

ant build java 7 -> run java 6 works

source code can now contain java 7 specific methods

[Till Schäfer]

Moving to "any feature version" because the necessary parts for 2.3.0 are implemented.
-> The tree map view is using java7 specific code and therefore we needed to ensure the java6 runtime compatibility when using a java7 compiler. The Compiler warnings are not visible in user experience. Making this bug a blocker for the release is therefore not desirable.