allow user to specify value for input forms

[sethfarns]

Often IRuby input users will want their forms to be prepopulated with what they entered the last time--can you add the options for users to specify that value, such as:

data = IRuby.form do input :my_input, label: 'Enter your input', value: 'Default value' end

[kylekyle]

Do you want to supply a default, or do you want the browser to suggest previous values that had been used in that input?

[jeffyjefflabs]

You can specify default values with :default, but see #122.