Pass linker options when loading *libraries* in GHCi.

Fixes #1439. See also #1435, which fixed this for executables.
Formatting.
Add 'suppressOverrideArgs'.
Ignore 'ghc-options' when parsing 'ghc --info' output.

Fixes #1438.
Rearrange the code a bit.
Rename 'pref' to 'libTargetDir'.
Merge pull request #1441 from 23Skidoo/repl-extralibs

Pass linker options when loading *libraries* in GHCi.
Merge pull request #1440 from 23Skidoo/ghc-info-ignore-ghc-options

Ignore 'ghc-options' when parsing 'ghc --info' output.