Added translation of some new strings and svg file of South Korean flag.

Flag of South Korea is from
http://commons.wikimedia.org/wiki/File:Flag_of_South_Korea.svg

Users can now clear the chat in the main lobby. This removes unwanted
text and clears up memory when the client has been open a long time.

+ Added the ability to see the account age of registered users. Changes
are both in server and client. The server will now send back the
registration date along with the user data. The client will then use
this to calculate the account age and display it in the user details
window.

+ added time stamps to the in game chat

Fixed a non-standard word (손패) into the word that is used in official
translation (손)

Remove some duplicated code.

Added line breaks in Korean translation for better readability.

Edited several sentences after a third-party review

Fixes the "Card preview window gets stuck and can't be removed" issue by saving the cardname, instead of getting it back from the popup (with possible issues with case sensitivity). Also closes an old popup when a new is created.

 * Always install “release” plugins
 * install only plugins actually used

Missing tooltip

We previously parsed only .cpp files, but some strings are inlined in
header files.

Drop CardInfo’s own pixmap caches; use QPixmapCache instead.
Use QPixmap references instead of pointers.
Being stored in QPixmapCache, all card images are now subjected to
QPixmapCache’s size limit

ucfirst(setCode): requires oracle re-run
reorder columns
rename the “short name“ column as “set code“
ensure proper casting for releaseDate and sortKey fields (refs 00a5ed0b)