Fix classpath unit tests

This fixes unit test errors caused by different path separators on Windows
operating systems.
Added ignoreVersionCheck for skipping the check for a supported Android Plugin.
Added 1.0.0-rc1 to the list of supported Android Plugin versions.
Merge pull request #105 from friederbluemle/fix-unit-test

Fix classpath unit tests.
Merge pull request #111 from ChristianBecker/cb/ignoreVersionCheck

Added ignoreVersionCheck for skipping the check for a supported Android Plugin.