qt: register metatype for bool*

This allows the bool* type to be passed between threads.  Should solve issue #2402.
aboutdialog: use just "The Bitcoin developers" as tr()-string

- this ensures our new splash screen and this will share a translatable
  string an remove the need for an additional translation
bitcoin: use static QApplication:: instead of app.
bitcoingui: remove 2 unneeded includes
overviewpage: make some code Qt5 compatible

- that changes will be fine for Qt4 also
Merge pull request #2525 from laanwj/2013_04_metatypebool

qt: register metatype for bool*
Do not invoke DoS for non-canonical sigs
Merge pull request #2540 from sipa/nodosnocan

Do not invoke DoS for non-canonical sigs
Update osx build instructions to ensure users link to the correct version of OpenSSL
Merge pull request #2546 from fanquake/osx-instructions

Update osx build instructions to ensure users are building with the correct version of OpenSSL when using HomeBrew
Add bitcoin-qt.pro homebrew patch
Update Qt Readme to include HomeBrew setup for OSX
Update Tor.txt for grammar fixes
Merge pull request #2556 from APerson241/master

Some small grammar fixes
Merge pull request #2526 from Diapolo/Qt_misc

Bitcoin-Qt: misc small changes
Reduce number of open LevelDB files to 64
Merge pull request #2557 from sipa/leveldb64

Reduce number of open LevelDB files to 64
Merge pull request #2554 from fanquake/qt-pro-brew-patch

bitcoin-qt.pro Brew patch
translations update 2013-04-25

- new language "se"
- update bitcoin.qrc and bitcoin_en.ts
- fetch current translations from Transifex
Merge pull request #2563 from Diapolo/translations

translations update 2013-04-25