Don't create empty transactions when reading corrupted wallet

The current transaction loading code is not exception safe.
An exception during deserialization causes an empty transaction
to be left behind in the wallet.

Fix this by building the transaction separately and adding
it only to the wallet at the end.

Fixes #3333.
build: Update the other win32 deps

- miniupnpc-1.8
- openssl-1.0.1e
- zlib-1.2.8
- libpng-1.6.8
- qrencode-3.4.3
build: upgrade Qt used by windows build to 5.2.0
build: use Ubuntu 12.04 for linux gitian build
[Qt] add missing lock in walletmodel
[Qt] 2 minor translation changes
[Qt] small paymentserver header cleanup
Merge pull request #3540

57d8e3f [Qt] add missing lock in walletmodel (Cozz Lovan)
Merge pull request #3541

c704532 [Qt] small paymentserver header cleanup (Philip Kaufmann)
Merge pull request #3538

81bad8b [Qt] 2 minor translation changes (Philip Kaufmann)
Merge pull request #3426

16ec904 Don't create empty transactions when reading corrupted wallet (Wladimir J. van der Laan)
doc: bump boost version in release-process

This was forgotten in #3501.
gitian: add explicit dependency build for linux

Create a dependency file per architecture:

- bitcoin-deps-linux32-gitian-r1.tar.gz
- bitcoin-deps-linux64-gitian-r1.tar.gz
Merge pull request #3527 from laanwj/2014_01_gitian_win32_qt5

build: update win32 deps
Merge pull request #3536

0425715 gitian: add explicit dependency build for linux (Wladimir J. van der Laan)
279af1a build: use Ubuntu 12.04 for linux gitian build (Wladimir J. van der Laan)