project: Improve Project Tagging.

* 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.
remove unused method test
Merge pull request #44 from npcode/feature/new-tagging

project: Improve Project Tagging.
logging: Add Logging feature

* Use conf/application-logger.xml as configuration for logging, instead
  of application.conf.
* Log application and play log in logs/application.log, access log in
  logs/access.log and every log in logs/root.log.
* Add a user document about logging.
fix userinfo dropdown style of topmenu
apply HIVE CSS including trivial fix. delete milestone manage page that combined with milestone list page
code history, diff view UI fixed (HIVE-146, HIVE-145)
Merge pull request #49 from wansoon/DOC_USER

User 클래스 javadoc 추가 및 리팩토링
added JavaDoc and refactoring GitRepository class
Merge pull request #54 from keesun/javadoc/git-repository

[JavaDoc] GitRepository
Merge pull request #51 from npcode/feature/logging

logging: Add Logging feature
doc/access-control: Update some about temp files.

임시 파일 -> 사용자에게 첨부된 파일
doc: Add Common Coding Style Guide.
Merge pull request #55 from npcode/doc/common-coding-style-guide

doc: Add Common Coding Style Guide.