* Make "Exchange" option in account setup depend upon availability of the
Exchange EmailService
* Make presence of Exchange logging depend upon availability of the
Exchange EmailService
* Make AttachmentDownloadService use service rather than ExchangeService
class
* Move SSLUtils to emailcommon/utility
* Move account manager type defs to emailcommon/AccountManagerTypes
* Update proguard.flags
* This is the penultimate CL for the Email package itself; the next CL
creates a clean, SDK-compatible Email application
Bug: 3442973
Change-Id: I9162cf5fa6b5a043ded0fdd1e25fd3ce5948ad8f
