all: clean up lint issues, remove more dead code

mobile: rename passphrase signing method to avoid Swift rewrite

The crash when compiling stdin was fixed in solc 0.3.6 (released
2016-08-10). While here, simplify the test so it runs with any solc
version.

Fixes #3484. The byte code was different for each run because recent
solc embeds the swarm hash of contract metadata into the code. When
compiling from stdin the name in the metadata is constant.

core/types: remove redundant SignECDSA wrappers, rename to SignTx

core/types: dependency cleanup

This removes the core/types -> leveldb dependency.

This significantly reduces the dependency closure of ethclient, which no
longer depends on core/vm as of this change.

All uses of vm.Logs are replaced by []*types.Log. NewLog is gone too,
the constructor simply returned a literal.

params is imported by leaf-ish library packages and should not pull in
the p2p stack.

build: finally settle on empty iOS ObjC package prefixes

Account management API polishes

core,cmd/utils: bugfix for ropsten dump imports

The run loop, which previously contained custom opcode executes have been
removed and has been simplified to a few checks.

Each operation consists of 4 elements: execution function, gas cost function,
stack validation function and memory size function. The execution function
implements the operation's runtime behaviour, the gas cost function implements
the operation gas costs function and greatly depends on the memory and stack,
the stack validation function validates the stack and makes sure that enough
items can be popped off and pushed on and the memory size function calculates
the memory required for the operation and returns it.

This commit also allows the EVM to go unmetered. This is helpful for offline
operations such as contract calls.

To address increasing complexity in code that handles signatures, this PR
discards all notion of "different" signature types at the library level. Both
the crypto and accounts package is reduced to only be able to produce plain
canonical secp256k1 signatures. This makes the crpyto APIs much cleaner,
simpler and harder to abuse.

cmd/utils, eth, les: bubble --fakepow flag into eth/les too

ethclient: hex encode request args for TransactionInBlock

ethclient: pass ptr when parsing eth_getTransactionByHash result

eth: fix miner start API to accept int, not hexint

rpc: remove HexBytes, HexNumber

mobile: fix ropsten chain configs