Merge branch 'master' into feature/apache-compress

...y/src/com/oracle/truffle/r/library/utils/TypeConvert.java

...ry/src/com/oracle/truffle/r/library/utils/WriteTable.java

...des/builtin/base/system/ProcessSystemFunctionFactory.java

...e/truffle/r/nodes/builtin/base/system/SystemFunction.java

...le/truffle/r/nodes/access/variables/ReadVariableNode.java

....r.runtime/src/com/oracle/truffle/r/runtime/RRuntime.java

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

.../oracle/truffle/r/test/library/utils/TestTypeConvert.java

...m/oracle/truffle/r/test/library/utils/TestWriteTable.java