#32 base_text::trim

[pavel kropitz]

i would like to propose setter base_text::trim that will trim (like boost::trim) the value_ in base_text::load, so the base_text::limits and base_text::non_empty will validate input text properly for my use case :).

it is default behaviour for oneline inputs (except password) in nette framework, for example.

"Logical Fallacy of Argument by Lack of Imagination": i have a hard time to imagine use case (in web environment), when for any base_text derived widget non-trimmed value would be desired, except password and performance.