expose line info at error; workflow updates

[chenyong]

Now errors are displayed with line numbers, for example:

/Users/chen/repo/cirru/parser.coffee/lib/parser.js:209
  throw new Error(`${prefixError(state)} open parenthesis in token`);
  ^

Error: cirru/folding.cirru(6:10) open parenthesis in token
    at _token_open (/Users/chen/repo/cirru/parser.coffee/lib/parser.js:209:9)
    at parse (/Users/chen/repo/cirru/parser.coffee/lib/parser.js:346:20)
    at Object.exports.parse (/Users/chen/repo/cirru/parser.coffee/lib/parser.js:24:33)
    at Object.exports.pare (/Users/chen/repo/cirru/parser.coffee/lib/parser.js:35:17)
    at test (/Users/chen/repo/cirru/parser.coffee/test.cirru:11:20)
    at Array.forEach (<anonymous>)
    at Object.<anonymous> (/Users/chen/repo/cirru/parser.coffee/test.cirru:24:7)
    at Module._compile (internal/modules/cjs/loader.js:1256:30)
    at Object.<anonymous> (/Users/chen/repo/cirru/parser.coffee/node_modules/cirru-script/lib/command.js:90:14)
    at Module._compile (internal/modules/cjs/loader.js:1256:30)