Bump version numbers for 0.8 release

Version numbers changed from 0.7.99 to 0.8.0
Set CLIENT_VERSION_IS_RELEASE to remove pre-release warning
Updated copyright in COPYING and doc/READMEs to 2013
Updated doc/release-notes.txt
Signrawtransaction shouldn't require redeemScript for non-p2sh txins.

The redeemScript functionality broke plain offline signing, this
change makes it only look for that parameter when signing a p2sh
input.
Do not call ResendWalletTransactions when reindexing, importing or on IBD

Calling ResendWalletTransactions when reindexing, importing or on IBD spams
other nodes with our old transactions, because they become unconfirmed.
Bugfix CValidationResult for BIP30 + add DoS
Merge pull request #2259 from Criptomonedas/dontresend

Do not call ResendWalletTransactions when reindexing or importing
Merge pull request #2264 from gmaxwell/signrawtransaction_for_regular_missing_txins

Signrawtransaction shouldn't require redeemScript for non-p2sh txins.
Merge pull request #2279 from sipa/cvrbip30

Bugfix CValidationResult for BIP30 + add DoS
Merge commit 'd38c6488d067c2e88726e2ca99bc76fd67dab49b'
translations update (bitcoinstrings.cpp + bitcoin_en.ts)
Do not use C++11 std::vector.data()

std::vector.data() is a C++11 feature that makes my OSX build machine unhappy.
Use QImage.bits instead of QImage.constBits to ease backporting

Image.constBits was introduced in Qt 4.7.  Should be ok here to use
QImage.bits which allows linking against the Qt in Squeeze.
Merge pull request #2289 from laanwj/201301_qimage_bits

Use QImage.bits instead of QImage.constBits to ease backporting
Add script to clean up datadirs
Some improvements to the release notes
Merge pull request #2297 from sipa/notes

Some improvements to the release notes
Merge pull request #2295 from sipa/tidydir

Add script to clean up datadirs
Merge pull request #2286 from gavinandresen/fix2285

Do not use C++11 std::vector.data()
Pass compiler flags down into leveldb make

Fixes issue#2288. Includes cleanups from Luke's pull 2243.
Minor build fixes

Two changes: make some linux-specific linker options linux and linker specific.
And in the cross-compile environment, prefer the $HOME/qt/bin tools to
whatever might be somewhere else in the path.
Merge pull request #2283 from Diapolo/translations

translations update (bitcoinstrings.cpp + bitcoin_en.ts)