addText method does not honor the 'std' argument for default values

[phpmypython]

when adding a text field and providing the arg 'std' with a default value that value does not show when the box is rendered. The show method will only output a saved value for a field and never looks for the std arg as far as i could tell. I modified the show method for the text box with a small ternary that checks if the $meta is blank and if it is it will set the value equal to the std array key value. I'm sure there's another way you would like to fix this but i can submit a pull request with what i have if you want.