Adding ColMeans and updating ColSums.

...src/com/oracle/truffle/r/nodes/builtin/base/ColMeans.java

.../src/com/oracle/truffle/r/nodes/builtin/base/ColSums.java

...s/src/com/oracle/truffle/r/nodes/builtin/base/R/colSums.R

...src/com/oracle/truffle/r/nodes/builtin/base/RowMeans.java

.../src/com/oracle/truffle/r/nodes/builtin/base/RowSums.java

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

...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/simple/TestSimpleBuiltins.java

mx.fastr/copyrights/overrides