Remove token union unused integer field
Move turtle_lexer.h include earlier so YYSTYPE can be found
Replace turtle_parser_lval with yylval
Remove turtle_lexer_lex prototype / header override

No longer use YYDECL - the default works.
Add %option bison-bridge
Remove YY_DECL
Bison 3.0 the turtle parser

- Use bison 3.0+ directives replacing all command line arguments
- Update lexer and parser parameters (remove use of YYLEX_PARAM)
- (turtle_parser_error): Add scanner arg.
- Use rdf_parser argument directly rather than via casted variable.
- Add %empty directives
- Remove casts to raptor_parser* that are no longer needed
- (turtle_parse): Pass in scanner
Bison 3.0 the parsedate parser

- Update to new directives
- Set %param
- Update error call
Add bison 3.0 directives
Alter configure to accept bison 3.0.0 or newer, no yacc
Remove redundant declaration of turtle_lexer_lex
(raptor_parse_date): No need for cast to void* for yyparse
Provide missing flex prototypes for flex 2.5.35 or earlier
Revert test for missing prototypes; it's debian specific
Merge pull request #12 from dajobe/bison3.0-new

Switch to use and require Bison 3.0