Remove std::.
Import directive.
Multi-source and multi-contract compiler.
Improved external interface for multi-source and multi-contract compilation.
Merge remote-tracking branch 'ethereum/develop' into sol_import

Conflicts:
	libsolidity/CompilerStack.cpp
	libsolidity/CompilerStack.h
	solc/main.cpp
Renamed url to identifier and added some comments.
Comments and braces.
Avoid overwriting messages with same expiry.
Evade networking crash.
Merge remote-tracking branch 'ethereum/develop' into sol_import

Conflicts:
	libsolidity/CompilerStack.cpp
	libsolidity/CompilerStack.h
	libsolidity/InterfaceHandler.cpp
	libsolidity/InterfaceHandler.h
	solc/main.cpp
	test/solidityJSONInterfaceTest.cpp
	test/solidityNatspecJSON.cpp
Merge pull request #558 from chriseth/sol_import

Solidity for multiple files and multiple contracts per file.
Compile fix.
Merge pull request #576 from chriseth/sol_compilefix

Compile fix. Over-the-shoulder review by @lefterisjp.
Calling functions of other contracts.
Merge pull request #563 from chriseth/sol_callingContracts

Calling other contract's functions.
Merge branch 'develop' into network