Added option to pass jvmArgs.

https://github.com/robolectric/robolectric-gradle-plugin/issues/46
Merge pull request #62 from Snapchat/jvmargs_patch_v2

Added option to pass jvmArgs.
Changed include() and exclude() to accept varargs.
This is more generalized, and is consistent with the org.gradle.api.tasks.testing.Test API.
Merge pull request #63 from Snapchat/varargs_include_exclude

Changed include() and exclude() to accept varargs.
Support android gradle plugin 0.13.x.
Merge pull request #69 from erd/android-gradle-plugin-0.13

Support android gradle plugin 0.13.x.
Support project flavors for the android-library plugin

When this code was originally written, flavors were not supported by the android-library plugin. As such, when building a variation name, an optimization was put in place to skip the flavor as a piece of the ultimate variation name in the case of the android-library plugin. Now that flavors are supported for libraries, this optimization actually breaks the roboelectric plugin with an error such as "Error:Cannot add a SourceSet with name 'testDebug' as a SourceSet with that name already exists.". This is because a library today that *does* have flavors will cause this plugin to attempt to add the same-named test sourceset for each flavor+buildtype.
Testing test-task creation for android app and library flavors.
Add jvmArgs documentation to README.
Merge pull request #71 from kageiit/add_jvmargs_readme

Add jvmArgs documentation to README.
Merge pull request #70 from samdozor/support-library-flavors

Support project flavors for the android-library plugin.
Bump version number to 0.13.1.
Fix for APK splits
Merge pull request #77 from frownlee/apk-splits

Fix for APK splits.
Set source and target compatibility to 1.6.
Bump version number to 0.13.2.
Add extension properties for test parallelization.
Use HTTPS for Gradle Wrapper for better security.
Updated Android Gradle plugin to 0.13.2
Updated Travis configuration