通讯录部分改进

1.微调了样式
2.将添加条目与修改条目的按钮合并为一个
3.添加条目或者修改条目后，及时刷新使通讯录完整（暂未用AJAX）
待做：搜索，将通讯录用AJAX刷新，样式改动
Merge branch 'master' of https://github.com/ELWG-FE-Study/ELWGLife

Conflicts:
controllers/contact_controller.php
controllers/duty_controller.php
css/duty.css
js/duty.js
models/contact_model.php
models/duty_model.php
page/contacts.php
page/duty.php
views/duty/duty_body.php
views/duty/duty_footer.php
views/duty/duty_header.php
views/duty/dutyhead.php
views/duty_view.php
views/partial/contact_content.php
Merge branch 'master' of https://github.com/ELWG-FE-Study/ELWGLife

Conflicts:
	css/duty.css
	js/duty.js
	views/duty/duty_body.php
	views/duty/duty_footer.php
	views/duty/dutyhead.php
	views/duty_view.php
	views/partial/contact_content.php