Fixed ** hash expansion change between 2.1 and 2.2
Fixed ** hash expansion change between 2.1 and 2.2

In Ruby <= 2.1, keys in expanded hashes that are duplicates of keys
already in the hash are ignored.  In Ruby >= 2.2, the last value for a
particular hash key take precedence regardless of whether or not is is
literal or expanded by **.

sgarciac/spec,ruby/spec,sgarciac/spec,yous/rubyspec,askl56/rubyspec,benlovell/rubyspec,wied03/rubyspec,bl4ckdu5t/rubyspec,kidaa/rubyspec,yous/rubyspec,kachick/rubyspec,kachick/rubyspec,iliabylich/rubyspec,kidaa/rubyspec,BanzaiMan/rubyspec,lucaspinto/rubyspec,sgarciac/spec,nobu/rubyspec,benlovell/rubyspec,eregon/rubyspec,eregon/rubyspec,kachick/rubyspec,nobu/rubyspec,jannishuebl/rubyspec,wied03/rubyspec,BanzaiMan/rubyspec,wied03/rubyspec,ruby/spec,ruby/rubyspec,eregon/rubyspec,askl56/rubyspec,jannishuebl/rubyspec,ruby/spec,ruby/rubyspec,lucaspinto/rubyspec,nobu/rubyspec,iliabylich/rubyspec,bl4ckdu5t/rubyspec