Fix TLS handshake failure during download

[kianmeng]

Use 'ciphersuite_strong' in the TLS manager to resolve handshake failures (DecodeError) due to rejection of weak cipher from remote server when building database through hoogle generate.

Before:

$ hoogle generate                                                               
                                                                                                            
Starting generate                                                                                           
Downloading https://www.stackage.org/lts/cabal.config... hoogle: Uncaught exception http-client-0.7.19-e53e031a3080635351a782ae473941335ff5cb434b654af0da963246f7167366:Network.HTTP.Client.Types.HttpException:
                                                                                                            
HttpExceptionRequest Request {                        
  host                 = "www.stackage.org"
  port                 = 443
  secure               = True
  requestHeaders       = []
  path                 = "/lts/cabal.config"
  queryString          = ""
  method               = "GET"
  proxy                = Nothing
  rawBody              = False
  redirectCount        = 10
  responseTimeout      = ResponseTimeoutDefault
  requestVersion       = HTTP/1.1
  proxySecureMode      = ProxySecureWithConnect
}
 (InternalException (HandshakeFailed (Error_Protocol "expecting server hello, got alert : [(AlertLevel_Fatal,DecodeError)]" HandshakeFailure)))                                                                          

While handling HttpExceptionRequest Request {
  |   host                 = "www.stackage.org"
  |   port                 = 443
  |   secure               = True
  |   requestHeaders       = []
  |   path                 = "/lts/cabal.config"
  |   queryString          = ""
  |   method               = "GET"
  |   proxy                = Nothing
  |   rawBody              = False
  |   redirectCount        = 10
  |   responseTimeout      = ResponseTimeoutDefault
  |   requestVersion       = HTTP/1.1
  |   proxySecureMode      = ProxySecureWithConnect
  | }
  |  (InternalException (HandshakeFailed (Error_Protocol "expecting server hello, got alert : [(AlertLevel_Fatal,DecodeError)]" HandshakeFailure)))                                                                      

HasCallStack backtrace:
  throwIO, called at ./Control/Monad/Trans/Resource.hs:195:13 in resourcet-1.3.0-7299c6173b690f5eb16d3064231923041dd3dc557a27f9dbaf609a7a01dc2448:Control.Monad.Trans.Resource         

After:

$ hoogle -- generate
Starting generate
Downloading https://www.stackage.org/lts/cabal.config... 1.41s
Downloading https://www.stackage.org/nightly/cabal.config... 1.43s
Downloading https://raw.githubusercontent.com/haskell/haskell-platform/master/hptool/src/Releases2015.hs... 1.10s
Downloading https://hackage.haskell.org/packages/index.tar.gz... 5m08s
Downloading https://hackage.haskell.org/packages/hoogle.tar.gz... 
...