Bump version to 10.4
Use icons for the tabs in the main screen. Bump version to 10.4.991.
Fix detail screen last/next date saving bugs.
Squashed commit of the following:

commit cea26ba38a4be8a9d3f954cdc03d6f0cc1549313
Merge: 2cb4004 ceeb1cc
Author: Howard Liberty <liberty@anymemo.org>
Date:   Mon Apr 7 12:53:15 2014 -0700

    Merge branch 'yijing-branch' of https://code.google.com/p/anymemo into yijing-branch

commit ceeb1cc106e37b3aea35250ef647fb70d987adb5
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Mar 15 15:31:04 2014 -0400

    Delete DownloaderQuizler and refactory API_ENDPOINT

commit e40a9b4370355e3051ccfc7e654e03f75eedc17e
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Mar 15 14:34:44 2014 -0400

    Resolve space format problem

commit 92eea238d20b0603d8d9474bb2dd1622981921e8
Merge: 40a665a 0b82a46
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Mar 8 16:18:03 2014 -0500

    Merge branch 'master' into yijing-branch

commit 40a665a969dd18715de1d5d6f98b8ce0f69cf84e
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Mar 8 16:15:26 2014 -0500

    Refactory public Quizlet cardset download

commit f892f99763dbf5f3926d14a1941e752bd2e84be8
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Mar 1 20:44:36 2014 -0500

    Refactory Quizlet public card search by title and user name functions

commit fb9764b961969307340e31cdc6f0e52a10fe3c8a
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Feb 22 18:59:38 2014 -0500

    Refresh Quizlet Cardset List once successfully uploaded a db

commit 2cb4004afaf3356a2b7b63f8a10885b727b52037
Merge: 107c864 ebc98db
Author: Howard Liberty <liberty@anymemo.org>
Date:   Sat Feb 22 13:03:38 2014 -0800

    Merge branch 'master' into yijing-branch

commit 147744bfa61847d28dcd1ad85325a6f4baeb1a3e
Merge: 107c864 ebc98db
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Feb 22 15:40:48 2014 -0500

    Merge branch 'master' into yijing-branch

commit 107c864a34e9d174e2acf023a10613508929158f
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Feb 22 15:02:06 2014 -0500

    Modify the QuizletUploadHelper class's makePostApiCall function

commit 5b05ecc011677e32d9d0ad871e4b29e158a6ed87
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Feb 15 17:53:09 2014 -0500

    Refactory QuizletUploadHelper

commit 6348a4f4ecadabc03501b3d41f5d9bad92210967
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Feb 8 14:37:41 2014 -0500

    Add loadMore and hasMore to CardsetsListFragment.java

commit e7c0f5ae3d4e459301f656bf1e829ddb6ad2cd47
Merge: 7f9cf0b 724e438
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Feb 8 14:19:26 2014 -0500

    Merge branch 'master' into yijing-branch

    Conflicts:
    	res/values/strings.xml
    	src/org/liberty/android/fantastischmemo/AMEnv.java

commit 7f9cf0b30bd466545246512d7897275f5bfc0778
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Feb 8 13:41:38 2014 -0500

    Add the QuizletUploadHelper class

commit 9aeb528a6de9c571d8659359ff62c00b6f9dadd4
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Jan 25 16:46:56 2014 -0500

    Refactory download logic to QuizletDownloadHelper

commit 2e65814733ec46ba05885ff469ae0decf5ed38df
Merge: 781971e 31c59b6
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Jan 25 14:39:39 2014 -0500

    Merge branch 'master' into yijing-branch

    Conflicts:
    	res/values/strings.xml
    	src/org/liberty/android/fantastischmemo/AMEnv.java

commit 781971ef9bcf66f7f1d824d1cb67ec88194e6df4
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Jan 18 18:06:18 2014 -0500

    Upload the database to Quizlet:

commit b3ea2dabecefc757f376b49082c172b3a2aa0262
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Jan 11 19:09:21 2014 -0500

    Add the uploadToQuizlet function in the QuizletUploadActivity

commit 68ae828044dc539903f83d9cadadd1523d589607
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Jan 4 17:57:44 2014 -0500

    Add QuizletUploadActivity class

commit ebad4ac0b99eae80a70857a08d59c02d7476a2ff
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Dec 28 17:25:19 2013 -0500

    Add download function for Quizlet

commit 44dd1511290b8a02552c8ad532c56c83990e2c7b
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Dec 14 17:49:00 2013 -0500

    Modify the cardsetsListFragement.

commit b8c0617d207badf26684e42d7bf9b61b8f9636e3
Merge: d52689b 8639d42
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Dec 14 16:15:52 2013 -0500

    Merge branch 'master' into yijing-branch

    Conflicts:
    	res/values/strings.xml

commit d52689baedfdfcfd34e3b33b090d1013cfcc33f6
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Dec 14 16:08:01 2013 -0500

    Change cardsetsListFragment to get the information of quizlet sets.

commit 92399a45be5d9463c3f6bb4228c5173da4a65d5a
Merge: ce73448 3cb1fbb
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Nov 30 17:00:00 2013 -0500

    Merge branch 'master' into yijing-branch

commit ce7344853b8c257af821c503ef63d307eab2c8f1
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Nov 30 13:46:49 2013 -0500

    Add the files for Quizlet sets

commit e55e405e8864bec0d37e57fb8e23519ba56f3706
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Nov 30 13:42:36 2013 -0500

    Add CardsetsListFragment function to show the sets in Quizlet

commit e8b017bbf6bbbda0a3723d7e2f0556e729ab64c4
Author: Yijingzeng <zengyijing1990@gmail.com>
Date:   Sat Nov 9 16:53:40 2013 -0500

    Add the oauth authentication activity to get the access token.
Fix commons-io reference issue in quizlet card list fragment.