Tweaked and extended PHPDoc coverage in scbAdminPage.
Got rid of extract() in scbAdminPage methods.
Adjusted scbAdminPage->submit_button() PHPDoc to reflect accepting array as first argument.
Improved formatting of extended PHPDoc description for scbAdminForm->form_wrap()
Merge pull request #22 from Rarst/adminpage-tweaks

scbAdminPage tweaks
Refactored scbAdminForm->submit_button() to use get_submit_button().
Added support for passing <button>tag to scbAdminPage->form_wrap()
Fixed parsing arguments when not passed as array in scbAdminPage->submit_button()
Merge pull request #23 from Rarst/submitbutton-refactor

scbAdminPage->submit_button() refactored