[GR-4490] Allocations profiler adapted to the Truffle Allocation Profiling API.

...library/src/com/oracle/truffle/r/library/utils/Rprof.java

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

...tin/src/com/oracle/truffle/r/nodes/builtin/base/IsNA.java

...om/oracle/truffle/r/nodes/builtin/fastr/FastRInterop.java

...e/truffle/r/nodes/builtin/fastr/memprof/FastRprofmem.java

...uffle/r/nodes/builtin/fastr/memprof/FastRprofmemShow.java

...e/r/nodes/builtin/fastr/memprof/FastRprofmemSnapshot.java

...fle/r/nodes/builtin/fastr/memprof/FastRprofmemSource.java

.../nodes/builtin/fastr/memprof/MemAllocProfilerPrinter.java

...me/src/com/oracle/truffle/r/runtime/context/RContext.java

...e/src/com/oracle/truffle/r/runtime/data/RDataFactory.java

...untime/instrument/memprof/MemAllocProfilerInstrument.java

...e/r/runtime/instrument/memprof/MemAllocProfilerPaths.java

.../r/runtime/instrument/memprof/MemAllocProfilerStacks.java

documentation/allocprof.md