change view filename(HIVE-211), adjust project logo size(HIVE-213)
remove unused files, fix filter markup on milestone list

delete milestone manage page that combined with milestone list page

* Allow to edit tags on Overview page.
* Remove the tag editor on Project Setting page.
* Make tag has its own category.
* Add defeault tags.
* Add a document for Tag Typeahead API.

- make project name bold in project list page
- change project creation time expression to ago string

project: Owner must be a manager of own project.

* Owner cannot leave own project.
* Owner's role cannot be changed.

- display histories(issues, posts, commits)
- display project's source url and type.
- display closed and opend issue count
- display readme.md without regarding character's case.