refactoring #20
category selection fixed #20
newest discussion link is made #20
refactoring #20
link by mainId, subId #20
working well #20
String to static variables #20
#40 TimStanpの投稿に対応。roboMongoにて動作確認。表示は後ほど実装。
 #40 メソッド名の修正
refactor discussion dao #20
Merge origin/develop into develop
Merge master into develop
apply review #20
apply review2 #20
Merge pull request #51 from tAsktoys/ImplementLinkToNextPreviousPage

Implement link to next previous page
refs #20 supported variable context path for next/prev.
refs #50 Removed unused fields.
Added fixed link.
remove email from user #46
add javadoc to DiscussionDao.java