Minor GUI fixes and refactoring.
db.cpp: improve performance

Much faster, especially on systems with disk drives.
name_new dialog - more info
listtransactions fix, various GUI fixes.
* listtransactions now includes name operations
* transaction details (double-click) show correct amounts for name operations
* added address column in the name table (maybe need to make it hideable? It clutters the table)
* added address to the Configure Name dialog
* added red notice about 12 blocks delay to the Configure Name dialog
* "Expires in" now shows "pending" instead of empty cell
* value length in Configure Name limited to 519 bytes (due to limitation in CScript)
* HtmlEscape for names in the GUI
Merged latest commits from namecoin-qt.