Currently the build without implicitly included precompiled header
is not supported anyway (because Qt MOC source files do not include
stdafx.h, they include plain headers).
So when we decide to support building without implicitly included
precompiled headers we'll have to fix all the headers anyway.
Now instead of plain text a TextWithTags struct is used almost
everywhere. Started writing and reading serialized tags to drafts
from 9048, switched version to 0.9.48 for testing.
