Add photo view in log, fix bugs.
Add a new way to preview photo, but there's out-of-memory bugs.
Merge branch 'master' of https://github.com/bbdlg/FirstLog.git

Conflicts:
	FirstLog/AndroidManifest.xml
	FirstLog/res/layout/common_image_view.xml
	FirstLog/src/com/example/firstlog/LogListAdapter.java
	FirstLog/src/com/example/firstlog/PreviewImageActivity.java