Add DNS seed support for testnet
update and reformat README.md

* updated references to files which have since been moved
* added reference to licensing
* added brief summary in case a non-technical user happens upon repo first
* miscellaneous Markdown-isms to make the doc more attractive
* remove unused symlink README -> README.md

I double-checked the makefiles and whatnot to ensure that the README symlink is
not being referenced. It is not. Rather, `doc/README` and
`doc/README_windows.txt` are copied for distribution.
Bugfix: Enable ConnectBestBlock to properly report back validation problems, and ensure orphan processing (when their parents are found) cannot be used to counter-DDoS the node providing the parent

Also fix a minor typo
Bitcoin-Qt: better copyright year handling in AboutDialog

- this change allows us to keep the translation without the need to
  re-translate any string, when we update the copyright year
- copyright symbol is changed to HTML to ensure we get no encoding
  issues and it's removed from the translation string so translators don't
  break it by mistake
Merge pull request #2258 from Diapolo/Qt_copyright_about

Bitcoin-Qt: better copyright year handling in AboutDialog
translations update (bitcoinstrings.cpp and bitcoin_en.ts)
Merge pull request #2260 from Diapolo/translations

translations update (bitcoinstrings.cpp and bitcoin_en.ts)
Merge pull request #2257 from fanquake/docs

Update default URL in verify.sh
Make sure the genesis block is present after reindex
Merge pull request #2250 from colindean/doc/root-readme

update and reformat README.md
Merge pull request #2237 from petertodd/testnet-dnsseed

Add DNS seed support for testnet
Merge pull request #2253 from luke-jr/bugfix_valstate

Bugfixes for CValidationState
Make transactions larger than 100K non-standard

Extremely large transactions with lots of inputs can cost the network
almost as much to process as they cost the sender in fees.

We would never create transactions larger than 100K big; this change
makes transactions larger than 100K non-standard, so they are not
relayed/mined by default. This is most important for miners that might
create blocks larger than 250K big, who could be vulnerable to a
make-your-blocks-so-expensive-to-verify-they-get-orphaned attack.
Merge pull request #2273 from gavinandresen/txsize

Make transactions larger than 100K non-standard
Merge branch 'reindexgen' of git://github.com/sipa/bitcoin