Error tracking improvements

Improvements for easier error tracking:

1. Renamed `error.column` to `error.columnNumber` to match [corresponding Mozilla's property name](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error/columnNumber).
2. Added [`error.fileName`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error/fileName) property set from `options.source`.
3. Changed error format from `Error: Line [lineNumber]: [message]` to `[message] at [fileName|'<anonymous>']:[lineNumber]:[columnNumber]` for easier error tracking.

Those changes help to easier find file name and position where parsing error occurred which is especially helpful when parsing bunch of files asynchronously and getting only original error object in callback/event handler without linkage to name of file being parsed (i.e., gulp plugins).