Add arguments for timestamps columns names.

[samizdam]

Implement #576 && #706

[samizdam]

@robmorgan I don't sure, but this feature will be applied only after phar rebuilding?
Do I must push with pull request binary file?
Contributing FAQ not provide some info about it...

[shadowhand]

@samizdam please add tests.

[samizdam]

@shadowhand this method is already covered.
I'm update my branch with upstream now.

[robmorgan]

I dont really think we need this feature. If people want to change types etc or column names I generally tell them just to use addColumn() instead. I'd rather leave this method simple like Rails.

[shadowhand]

I don't see any problem with having defaults that can be modified rather than hard coded. Seems like a reasonable approach to me.

[rquadling]

I've implemented this feature, along with appropriate guarding of null (you cannot have a column called null - who'd have thought that!) and unit tests.