更新输入框提示符的实现方法，改用placeholder，去除js控制。
进一步更改相关的js和css。@boylee1111看一下
取消了对于build和diet文件夹的track，并清除了文件。pull这次更新之前请做好备份，不然可能需要revert
Merge branch 'master' of https://github.com/SmartEXPO/SmartEXPO

Conflicts:
	.gitignore
	SmartEXPO_Proj/build/web/WEB-INF/classes/com/smartexpo/models/Audio_.class
	SmartEXPO_Proj/build/web/WEB-INF/classes/com/smartexpo/models/Author_.class
	SmartEXPO_Proj/build/web/WEB-INF/classes/com/smartexpo/models/Comment_.class
	SmartEXPO_Proj/build/web/WEB-INF/classes/com/smartexpo/models/Description_.class
	SmartEXPO_Proj/build/web/WEB-INF/classes/com/smartexpo/models/ItemAudio_.class
	SmartEXPO_Proj/build/web/WEB-INF/classes/com/smartexpo/models/ItemAuthor_.class
	SmartEXPO_Proj/build/web/WEB-INF/classes/com/smartexpo/models/ItemComment_.class
	SmartEXPO_Proj/build/web/WEB-INF/classes/com/smartexpo/models/ItemVideo_.class
	SmartEXPO_Proj/build/web/WEB-INF/classes/com/smartexpo/models/ManagerPermission_.class
	SmartEXPO_Proj/build/web/WEB-INF/classes/com/smartexpo/models/Manager_.class
	SmartEXPO_Proj/build/web/WEB-INF/classes/com/smartexpo/models/Permission_.class
	SmartEXPO_Proj/build/web/WEB-INF/classes/com/smartexpo/models/Video_.class
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/Audio_.java
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/Author_.java
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/Comment_.java
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/Description_.java
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/ItemAudio_.java
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/ItemAuthor_.java
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/ItemComment_.java
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/ItemVideo_.java
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/Item_.java
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/ManagerPermission_.java
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/Manager_.java
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/Permission_.java
	SmartEXPO_Proj_new/build/generated-sources/ap-source-output/com/smartexpo/models/Video_.java
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/controls/InsertItemServlet.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/controls/InsertManagerServlet.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/jpgcontrollers/AudioJpaController.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/jpgcontrollers/DescriptionJpaController.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/jpgcontrollers/ItemAudioJpaController.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/jpgcontrollers/ItemVideoJpaController.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/jpgcontrollers/VideoJpaController.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/managedbean/LoginManagedBean.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/managedbean/SignUpManagedBean.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/managedbean/item/Audio.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/managedbean/item/Author.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/managedbean/item/Comment.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/managedbean/item/Description.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/managedbean/item/Video.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/Audio.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/Author.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/Comment.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/Description.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/Item.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/ItemAudio.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/ItemAuthor.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/ItemComment.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/ItemVideo.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/Manager.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/ManagerPermission.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/Permission.class
	SmartEXPO_Proj_new/build/web/WEB-INF/classes/com/smartexpo/models/Video.class
	SmartEXPO_Proj_new/build/web/WEB-INF/faces-config.xml
	SmartEXPO_Proj_new/build/web/item.xhtml
	SmartEXPO_Proj_new/build/web/sign_up.xhtml
	SmartEXPO_Proj_new/dist/SmartEXPO_Proj.war
	SmartEXPO_Proj_new/nbproject/private/private.properties