eth: fixed double close of channel. Fixes #2555

This fixes an issue where the following would lead to a panic due to a
channel being closed twice:

* Start mux
* Stop mux
* Sub to mux
* Unsub

This is fixed by setting the subscriptions status to closed resulting in
the Unsubscribe to ignore the request when called.

accounts/abi/bind: fix multi-value anonymous unmarshalling

README: fix typos

README: fix typos

accounts/abi: fixed unpacking in to already sliced interfaces

Previously it was assumed that wheneven type `[]interface{}` was given
that the interface was empty. The abigen rightfully assumed that
interface slices which already have pre-allocated variable sets to be
assigned.

This PR fixes that by checking that the given `[]interface{}` is larger
than zero and assigns each value using the generic `set` function (this
function has also been moved to abi/reflect.go) and checks whether the
assignment was possible.

The generic assignment function `set` now also deals with pointers
(useful for interface slice mentioned above) by dereferencing the
pointer until it finds a setable type.

cmd/geth: use text/templates in the tester, not html

cmd/geth, internal/web3ext, rpc: surface rpc module, fix shh, fix miner

travis: run CI builds against multiple Go versions

rpc: HTTP origin case insensitive

miner: fixed pending state by not shutting down update loop

cmd/utils: fix build on *BSD

build: add CI scripts for windows

core, eth, miner: improve shutdown synchronisation

Shutting down geth prints hundreds of annoying error messages in some
cases. The errors appear because the Stop method of eth.ProtocolManager,
miner.Miner and core.TxPool is asynchronous. Left over peer sessions
generate events which are processed after Stop even though the database
has already been closed.

The fix is to make Stop synchronous using sync.WaitGroup.

For eth.ProtocolManager, in order to make use of WaitGroup safe, we need
a way to stop new peer sessions from being added while waiting on the
WaitGroup. The eth protocol Run function now selects on a signaling
channel and adds to the WaitGroup only if ProtocolManager is not
shutting down.

For miner.worker and core.TxPool the number of goroutines is static,
WaitGroup can be used in the usual way without additional
synchronisation.

jsre: hotfix web3 for the console eth.syncing formatting

eth: fixed tracing functions using the current header instead of parent

Fixes #2525

Makefile: go build instead of install (solves cross compile issues)

node: start RPC/WS interface on localhost by default

internal/debug: also rename debug_startTrace to debug_startGoTrace

Also reduce log messages a little bit.

This was missing from the previous change.

internal/debug: rename debug_trace to debug_goTrace

Reduces confusion with EVM execution tracing methods.

cmd/geth: fixed to use proper version string for output