Fix Array#sample when pass count argument
Add Array#sample randomness specs
Remove Array#sample specs with high failury probability
Decrease failure probability for Array#sample randomness spec
Added spec suggested by miraks in #2792.
Merge remote-tracking branch 'miraks/array_sample_fix'
Removed questionable spec.
Note that not all standard libraries are implemented [ci skip]
Merge pull request #2822 from sferik/facts

Note that not all standard libraries are implemented
Add Tracer to the list of unimplemented libs [ci skip]
Add Continuation to the list of unimplemented libs [ci skip]
Add TracePoint to the list of unimplemented libs [ci skip]
Merge pull request #2823 from sferik/tracer

Add Tracer to the list of unimplemented libs
added string#scan benchmark and associated test file holmes.txt
Don't try to use lchmod() on linux, glibc has only a stub of lchmod(). Remove defines for XSH4.2 UNIX extensions from the test for lchmod(), there is no lchmod() in XSH4.2 and rbx is also not compiled with these defines.
Remove defines for XSH4.2 UNIX extensions from the test for lchown(), rbx is not compiled with these defines.
Replaced holmes.txt with benchmark/core/file/long.txt
Fixed apple file encoding so gcc might work as well as clang on this file
Merge pull request #2824 from kwleland/bench_scan

added string#scan benchmark and associated test file holmes.txt
String[]= benchmark added

also fixed file path in bench_scan.rb