Merge pull request #43 in G/fastr from ~MICK.JORDAN_ORACLE.COM/fastr:bugfix/modeltools-install to master

* commit '622ae26b':
  add stats4 package; fix DOTSXP serialization bugs

Merge pull request #44 in G/fastr from ~LUKAS.STADLER_ORACLE.COM/fastr:feature/post_merge_gate to master

* commit '66686d10':
  add gate runs "post-merge"

Merge pull request #41 in G/fastr from ~LUKAS.STADLER_ORACLE.COM/fastr:bugfix/various_changes3 to master

* commit '1c0d50c6':
  fix atanh builtin
  profile in FunctionDefinitionNode (whether ReturnException depth matches)
  simplify printing Utils

* commit 'bdce4250':
  Fix compile error

Merge pull request #38 in G/fastr from ~STEPAN.SINDELAR_ORACLE.COM/fastr:GR-131-remove-rdataframe to master

* commit '29ec23f3':
  Fix data frame tests
  Fix header in TestBuiltin_extract_dataframe
  Add extract data frame test expected outputs
  Remove unused RDataFrame related parameter from setVectorClassAttr
  create InheritsCheckNode in Bind
  Removed leftover commented code.
  Removed RDataFrame and remaining references to it.
  Removed data.frame specific code from CachedVectorNode
  Removed RDataFrame specific code from RSerialize
  Removed simple usages of RDataFrame
  Vector does not turn itself into RDataFrame

Merge pull request #39 in G/fastr from ~ADAM.WELC_ORACLE.COM/fastr:feature/r_caller_overhaul to master

* commit 'da57ed19':
  Folded RSyntaxNodeWrapper interface into (now also an interface) RCaller.
  Invalid caller is now a singleton.
  Fixed a copyright check.
  Regenerated tests.
  Traversing parent hierarchy in search for RCaller is no longer necessary at all and RCaller now has a typed representation.
  The mget function can now use functions as ifnotfound argument.
  Traversing parent hierarchy in search for RCaller is no longer necessary for call nodes.
  Fixed a caller of function called via do.call.
  Partial fix to the sys.call problem in the context of S3/S4.

Merge pull request #40 in G/fastr from ~LUKAS.STADLER_ORACLE.COM/fastr:bugfix/update_truffle to master

* commit '28624ea1':
  ignore warning context for lgamma test
  update Truffle dependency

Traversing parent hierarchy in search for RCaller is no longer necessary at all and RCaller now has a typed representation.

Added several unit tests for [.data.frame, which is the only function
from data.frame specific versions of [[, [, [[<-, [ that calls NextMethod,
i.e. transfers the control to CachedVectorNode

Removed RClass enum introduced in one of the previous commits,
for the time being the "data.frame" literal lives only in RRuntime
class together with static helper hasRClass

Also removed SEXPTYPE.FASTR_DATAFRAME, which was used only internally.
Data frames are serialized as any other RList.

those are checks like if (x instanceof RDataFrame) return x.getVector()

The trickiest is PrecedenceNode where we can get rid of check for RDataFrame,
because it is RList and gets the right precedence anyway, and CopyDFAttr with
many combinations of RDataFrame specializations.

Removed call to createDataFrame when RVector
gets data.frame class plus minimal changes that
make the current tests pass.

Merge pull request #37 in G/fastr from ~STEPAN.SINDELAR_ORACLE.COM/fastr:rattributes-refactoring to master

* commit '44f37189':
  Minor fix: use idiomatic RDataFactory.createEmptyStringVector()
  Moved getAttribute and getClassHierarchy to RAttributable interface

getAttribute was renamed to match the name of the existing
overload in the same interface.

Merge pull request #35 in G/fastr from ~STEPAN.SINDELAR_ORACLE.COM/fastr:inttobits-serialize to master

* commit '276dd760':
  Minor fixes from code review
  Regenerated expected outputs for tests
  RInternalError.shouldNotReachHere instead of assert and better utilization of testing infrastructure.
  Added missing header
  Failing test cases for issues discovered along the way
  Fixed RSerialize to accept RAbstractRawVector and have visible output
  added new built-in node intToBits