Two filtering options added to the RBuiltinDiagnostics allowing ignoring RNull and RMissing argument types.

Sampling code of the cast pipelines moved to com.oracle.truffle.r.nodes.casts package in module com.oracle.truffle.r.nodes.casts

Errors resulting from the preceding merge fixed

Filter expressions tested w.r.t performance

Copyrights added

A follow-up refactoring

Builtin verifier adapted to the refactored CP code

Builtin coverage analysis applied to the selected set of builtins

TypeExpr introduced to express the result types of the cast pipelines

Improved output of the builtin verifier prototype

Unit tests for TypeExpr and CastUtils.Casts.isConvertible

Splitting the argument filters in cast pipelines API to value and type filters.

Imports optimized

prototype of cast unit tests

Added capability of cast pipelines to provide positive and negative samples

Cast API passes the tests including the pipeline self-test

Tested features: fluent syntax, pipeline result types, positive and negative pipeline samples

Temporary comments removed from the builtins using Cast API

More comments removed

Some modifications of CastAPI following the review

Compilation warnings resolved

CastAPI names and FindFirst logic refactored

Cast API refactored and simplified

A little refactoring, EncodeString builtin using Cast API

A couple of "argument-heavy" builtins such as Scan adapted to the Cast API and some fine tuning of the API.

Using "and" filter operator in NGetText, the "missingValue" filter added, the MissingValue type handled in CastVectorNode

Null samples fixed

Checked the style

the scalarStringValue step added, the notNA steps copied to the initial phase

A couple of builtins use the new fluent cast builder

More builtins use the new cast builder

Another batch of builtins refactored using the new cast API

Copyright fixed

Type information retained by the cast pipelines

* commit '70743c95': (28 commits)
  update labsjdk to 0.15
  Minor fix: Choose use idiomatic Utils.incMod
  Fix checkstyle error
  Bind can handle when dimnames contains a scalar String
  Implement Internal 'choose'
  Fix: crossprod does not promote dimnames
  Fix: matrices multiplication preserves dimnames
  Fix drop builtin to support more scenarios
  Implement C_dnorm
  small cleanup in RCallNode
  minor cleanup
  handle RS4Object as envir argument in get/get0
  Fix TestRFFIPackage typo
  add/modify testrffi tests
  actually forward long timeout to FastRSession!
  checkstyle fix
  Increase timeout for package installation testing
  mx.fastr: fix sloppy argument checking
  mx_fastr: add back modified version of sanitizeVmArgs; up date ci.hocon
  BuildNative -> BuildJavaWithJavac
  ...