Retooled modal presentation.

Also made edits not auto-save when loggin in or creating
accounts from editing workflow, as it no longer makes
sense to do so with new editing workflow.

Made alerts work again with modals.

Got rid of extra scrolling beneath acct creation fields
when capcha interface isn't visible.

i18n for editing workflow "Preview" heading.

Tapping "Preview" label in editing workflow scrolls
preview section to top.

Change-Id: I2c2776e217f215de58fd51bb7eab0d6ba01d8caa
Merge "Retooled modal presentation."