Fix "Unable to load or use BouncyCastle provider." during unit tests.
Fix build.xml issues and improve it as well:
- Compile for java 1.6, not 1.5 as toad said we use 1.6 now. Change
JavaDoc link to 1.6 as well. I googled that link, I hope it is OK or
should it be a special link which aims to be used in ant build files?
- Fix ant warning "'includeantruntime' was not set"
- Don't copypaste classpaths, use <path refid="lib.path"/> instead
- Add missing target version to unit-test build. Don't copypaste version
1.5 in unit-test build, use variable instead