Untag passing spec and remove file
File.expand_path maintains the encoding of the path arg
Merge pull request #2579 from anupnivargi/file_path_encoding

File.expand_path maintains the encoding of the path arg
Don't assume byte length equality means ascii only

The string can still contain non ascii characters in the 128 - 255
range.
Untag passing specs
Added IO#write and IO.write specs for encoding
IO#write must write the encoded string when encoding is provided
Merge pull request #2580 from anupnivargi/io_write_fixes

IO#write must write the encoded string when encoding is provided
Use bytesize over size where possible for IO
Removed obsolete documentation symlink.
Fixed building with install prefix.
Merge remote-tracking branch 'origin/master' into compiler

Conflicts:
	kernel/common/load_order20.txt
	spec/tags/21/ruby/core/file/expand_path_tags.txt
	spec/tags/21/ruby/core/io/write_tags.txt