cmLinkLineComputer: Move ComputeLinkLibs from cmLocalGenerator
Add a cmOutputConverter to the cmLinkLineComputer and factory methods to facilitate shell escapes. Add state to the cmLinkLineComputer to record whether outputting for response files or for watcom, to satisfy the cmOutputConverter API. These are constant for the lifetime of the cmLinkLineComputer, even when its functionality is extended in the future. This also keeps the signatures of cmLinkLineComputer relatively simple. Pass the cmComputeLinkInformation as a method parameter so that cmLinkLineComputer is free from target-specific state. An instance should be usable for all targets in a directory.