remove obsolete and unused typedef for Windows
Remove leveldb in preparation for git-subtree
Squashed 'src/leveldb/' content from commit aca1ffc

git-subtree-dir: src/leveldb
git-subtree-split: aca1ffc4b65be5e099b2088c6e6a308d69e1ad73
Merge commit 'c25e98186d0f716451ef000e55646d25e014f573' as 'src/leveldb'
osx: make use of the 10.8+ user notification center to display growl like notifications

- if 10.8, use user notification center, if <10.8, use growl

Signed-off-by: Jonas Schnelli <jonas.schnelli@include7.ch>
Don't attempt to resize vector to negative size.
Merge pull request #2705 from robbak/crash_zero_size_peers.dat

Don't attempt to resize vector to negative size.
Merge pull request #2716 from laanwj/2013_05_30_getwork

Move pMiningKey init out of StartRPCThreads
Merge pull request #2615 from jonasschnelli/mac10_8_not_center

osx: make use of the 10.8+ user notification center to display growl lik...
Merge pull request #2552 from Diapolo/win-typedef

remove obsolete and unused typedef for Windows
Merge pull request #2616 from vinniefalco/leveldb-as-subtree

Leveldb as subtree
qt: allow user to choose data directory

This adds an introduction screen that is shown when the client is first
started in which the user can choose a data directory.

It is also possible to force the intro screen to appear using command
line argument `-choosedatadir`.

The user is warned that the client will download and store 10Gb of data.
The intro screen shows how much space is available on the device that
contains the chosen directory and warns if this is less than the 10Gb.

To make it possible to translate the introduction dialog, the initialization
sequence is changed so that translations are
loaded before the data directory. This has the by-effect that it is
no longer possible to specify a language in bitcoin.conf inside the data
directory.