fix so following a number with either . or e or E without whitespace
will cause a lexing error
remove */ from symbols in postgres (although postgres strictly
speaking allows this I think, it is not a good idea)
reject */ anywhere with an error
reject ||| (or more pipes) in ansi, etc. dialects instead of trying to
parse it as something like '||', '|'
add utility function to tell if two tokens will pretty print then lex
back to the same two tokens or not
add notes for some final missing lexing bits that are in hssqlppp
add token combo tests for postgres
add start of sql server, oracle and odbc lexing tests
fix positions?
small fixes to haddock
add notes to top of lexer module
simplify line comment lexer
remove some trys from lexer
fix the block comment parser to return all the comment text when there
are embedded / * in the comment
refactor the symbol, keyword and identifier blacklist checking into
the low level token parsers instead of a separate step using guard
