Depend on any java7 jre/jdk

Change the Build-Depends and Depends directives of the package to refer
to the relevant Java distribution that OpenJDK provides as an alternative,
rather than directly only to OpenJDK.

This allows any compatible Java distribution to fulfill the dependency
without placing a strict requirement on OpenJDK.

$ dpkg -I openjdk-7-jdk_7u55-2.4.7-1ubuntu1_amd64.deb | grep Provides
 Provides: java-compiler, java-sdk, java2-sdk, java5-sdk, java6-sdk, java7-jdk

$ dpkg -I openjdk-7-jre_7u55-2.4.7-1ubuntu1_amd64.deb | grep Provides
 Provides: java-runtime, java2-runtime, java5-runtime, java6-runtime, java7-runtime

Change-Id: I8c9b480521487a5a19f7813340472d99a88a112a
Merge "Depend on any java7 jre/jdk" into debian