add tests for “unserialize”, enable passing tests

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

.../com/oracle/truffle/r/test/builtins/TestBuiltin_args.java

...racle/truffle/r/test/builtins/TestBuiltin_asfunction.java

...le/truffle/r/test/builtins/TestBuiltin_bitwiseShiftL.java

...m/oracle/truffle/r/test/builtins/TestBuiltin_deparse.java

...m/oracle/truffle/r/test/builtins/TestBuiltin_digamma.java

...c/com/oracle/truffle/r/test/builtins/TestBuiltin_dim.java

...om/oracle/truffle/r/test/builtins/TestBuiltin_lgamma.java

...c/com/oracle/truffle/r/test/builtins/TestBuiltin_max.java

...c/com/oracle/truffle/r/test/builtins/TestBuiltin_min.java

...om/oracle/truffle/r/test/builtins/TestBuiltin_signif.java

...acle/truffle/r/test/builtins/TestBuiltin_unserialize.java

...acle/truffle/r/test/library/base/TestSimpleSequences.java

...oracle/truffle/r/test/library/base/TestSimpleVectors.java