merge

...c/com/oracle/truffle/r/nodes/access/ReadVariableNode.java

...com/oracle/truffle/r/nodes/builtin/base/RepeatLength.java

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

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

...le.r.test/src/com/oracle/truffle/r/test/all/AllTests.java

...t/src/com/oracle/truffle/r/test/failing/FailingTests.java

...com/oracle/truffle/r/test/generate/TestOutputManager.java

.../com/oracle/truffle/r/test/simple/TestSimpleBuiltins.java

...com/oracle/truffle/r/test/simple/TestSimpleFunctions.java

mx.fastr/mx_fastr.py