Minor doco changes

[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8362]
- Fixed begin w/ else but no rescue. (whitequark)
[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8363]
- Removed literal stripping from block_append. Not its job.
[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8365]
prepped for release
[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8383]
Added minitest path
[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8588]
Updated for minitest 5
[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8601]
! Added (rough draft) 2.0 support. Still missing some small / rare things.
+ Fixed rake to < 10, because 10's file dependency handling is so very broken.
+ Added compare20 rake task to diff the grammar architecture against MRI.
+ Switched `rake debug` to default to 2.0.
- Switched ruby_parse_extract_error to use binread.
- Fixed BEGIN {} to return a sexp.
- Fixed op_asgn nodes to #to_sym their args properly.
- Fixed block_command and block_call (eg a.b c d) to #to_sym their args properly.
- Fixed assoc args in 1.9.
- Cleaned up a LOT of arg handling (block and defn, not calls) by using #args.
- Fixed optional value block args.
- Fixed support for empty symbol (wtf?).
- Lexer is now declared UTF-8 internally. Hopefully this will fix the encoding mess.
- Extended IDENT_CHAR_RE on 1.9+ to top out at \u{10ffff}... because we NEED a million unicode chars.
- ESC_RE is set to unicode. This seems problematic. *shrug*
- Switched a number of lexical constructs to use IDENT_CHAR_RE instead of \w. I wish there were something cleaner for regexps + unicode.
+ Added %i(symbol-names...) support. (%I too)
- Apparently ruby doesn't warn for escaped octal that goes above 7. wtf.
- RubyLexer#unescape ignores bad octal/hex and returns unicode strings.
- Fixed arg_blk_pass to allow for sub-args nodes.
+ Added shadow nodes for scoped block args.
- Fixed assignable to allow for sexps to be passed to it.
- Made UTF_8 the default guess on encodings when it isn't explicit.
+ Added 140 more tests, jumping test count from 1376 to 2143. Yay for test reuse!

[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8669]
- Fixed a[] += b. (stormbrew)
[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8670]
RubyParser.for_current_ruby can now return Ruby20Parser instances
[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8671]
+ Refactored to RubyParserStuff::ENCODING_ORDER to allow custom tweaking of encoding guessing. (samlown)
[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8672]
+ Compound RubyParser now defaults to 2.0.
- Fixed bug in compound RubyParser so it rescues RubyParser::SyntaxError.
[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8673]
- Fixed parsing of __ENCODING__ on ruby 1.8 (vcall).
- Parsing of __ENCODING__ on ruby 1.9+ (in ruby 1.9+) is now colon2 sexp. (whitequark)
[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8674]
Added test_dstr_evstr_empty_end
[git-p4: depot-paths = "//src/ruby_parser/dev/": change = 8675]
Replace handwritten lexer with a Ragel-generated one.
Begin updating ruby20_parser.y for Ragel lexer.