Update llvm from 6.0.0-1 to 7.0.0

Remove lldb package

Add pre-built binaries

packages/lldb.rb

-require 'package'
-
-class Lldb < Package
-  description 'LLDB is a next generation, high-performance debugger.'
-  homepage 'http://lldb.llvm.org/'
-  version '3.6'
-  binary_url ({
-    i686: 'https://www.dropbox.com/s/bls4hv4z8m2ifsc/lldb-3.6-i386.tar.gz?dl=0',
-    x86_64: 'https://www.dropbox.com/s/zi3rzdmz2awu8u8/lldb-3.6-64x.tar.gz?dl=0'
-  })
-  binary_sha256 ({
-    i686: '7bdb9d0078aa0a6bd1d56df24e076a007a80274dbd0870b7d81a4a9767da49b2',
-    x86_64: 'ac81a42662a1fde6b6a0dfb9e81be93deefc4ef78f80e67114dfc6fcaf65f4fa'
-  })
-end