Merge pull request #28 from NetEase/develop

Emmagee 2.0
Update README.md and changelog.md
Update README.md
remove `libs` from build path; add .gitignore; ...

refactor ListAdapter;
Change settings to SharedPreferences from Properties;
set File name to mail attachment;
check read_logs permission
Merge branch 'yrom-master' into develop
Misc: code review