Thunderbird:UI Reduction

There's too much of it. It needs consolidation and simplification

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Not just consolidation and simplification, but also reorganization

For example, the options dialogue is poorly organized right now. Fonts and Display should be merged under Mail Display. Some of the options are used by very few users and should be ditched in favour of system default. The junk mail dialogue should be merged into options and grouped along with sanitization options, password options, certificates etc. under Junk Mail and Privacy. Return Receipts Options should be placed under Composition and Connection Settings should be placed under General (just like firefox).

The Account dialogue also needs a redesign. We should design something similar to firefox's Bookmark Manager with account grouped by their types (Email, Newsgroup and RSS) on the left pane and the specific settings on the right pane. By default, we will only have one pane with server settings, logins settings, folder settings (user local folder or individual folder), certificate settings and composition settings (html or plain text)