modify test project to avoid any dependence on files in src directories

.gitignore

com.oracle.truffle.r.test.native/Makefile

com.oracle.truffle.r.test.native/packages/Makefile

com.oracle.truffle.r.test.native/packages/package.mk

...acle.truffle.r.test.native/packages/tests4/lib/tests4.tar

com.oracle.truffle.r.test.native/urand/Makefile

...est/src/com/oracle/truffle/r/test/ExpectedTestOutput.test

...ruffle.r.test/src/com/oracle/truffle/r/test/TestBase.java

...uffle.r.test/src/com/oracle/truffle/r/test/TestRBase.java

...m/oracle/truffle/r/test/library/base/TestConnections.java

....test/src/com/oracle/truffle/r/test/rffi/TestUserRNG.java

...rc/com/oracle/truffle/r/test/rpackages/TestRPackages.java

...cle/truffle/r/test/rpackages/TestRecommendedPackages.java

mx.fastr/mx_fastr.py