add bitcoin core copyright to license

...and rearrange copyrights so that the most important ones are first. Since
this library at one point morphed into bitcore2, I place bitcore as the most
important extra copyright to indicate the importance of BitPay funding 4 or so
weeks of development of this project. Second is BitcoinJS, where some important
code comes from, such as BIP32 and public key recovery from a signature. Then
comes bitcoind, where the script interpreter is translated from. Finally is
BitcoinJ, which I have not personally referenced at all, but which is here
because it was in the original copyright for BitcoinJS.

The top copyright goes to myself and reddit. I own the trademark "fullnode"
since I created that name while independent and not working for anyone.
However, reddit owns the copyright on the code I am writing while under their
employment.
add info about coverage report and browser tests
add "expose everything" principle
add basic documentation to every major class

Ultimately I would like to document every method in the class, along with
refactoring things and making sure the interface is perfect. However, for now,
I have simply added a basic introductory-type comment at the top of every major
class. These comments show up when you run "groc" to build the documentation.
fix comment formatting for groc

groc, the tool we use to automatically generate HTML documentation, was
interpretering the < and > symbols as HTML, messing up the formatting. I have
replaced with with [ and ] which do not mess up the formatting.
v0.2.1