This also removes the powermock dependency. Although powermock is a
fine library, it currently prevents dropping Junit4. And since we only
use the Whitebox API of powermock, this simply replaced powermock's
Whitebox with our own.
The previously used approach of
project(':smack-core').sourceSets.test.runtimeClasspath
caused the 'eclipse' target to produce duplicate classpath entries in
.classpath when run with Gradle >= 2.6. It also relied on Gradle
internals.
Instead we now use
project(path: ":smack-core", configuration: "testRuntime")
project(path: ":smack-core", configuration: "archives")
to be able to use test classes from other subprojects (usually
smack-core) in e.g. smack-extensions. The 'archives' configuration
includes the test jar.
See also https://discuss.gradle.org/t/11784
Thanks to Lari Hotari for helping with this issue.
instead of using the old baseName=smack appendix=project.name approach,
we are now going convention over configuration and renaming the
subprojects directories to the proper name.
Having a prefix is actually very helpful, because the resulting
libraries will be named like the subproject. And a core-4.0.0-rc1.jar is
not as explicit about what it actually *is* as a
smack-core-4.0.0-rc1.jar.
SMACK-265
