Don't strip libraries in build directory

Two changes:

  * strip static libraries (.a files) at install/copy time, instead of
    at build time. Note that Cabal strips shared libraries (.so files)
    and executables at install/copy time also.

    This is needed for GHC, because it uses Cabal (via ghc-cabal copy)
    to install the boot libraries, and relies on Cabal to take of
    library stripping. Currently .so files indeed get properly stripped,
    but .a files do not.

    (Stripping static libraries at build time was introduced in
    60409cb9, with the explanation:
    "Call 'stripLib' from createLibArchive so that it's done only
    once.")

    This bug (if you want to call it that) partially explains the
    difference in size of a GHC installation before and after manual
    stripping, reported in
    https://github.com/haskell/cabal/issues/1622#issuecomment-62076817
    (The other parts are that the GHC build system currently doesn't
    strip executables on installation:
    https://ghc.haskell.org/trac/ghc/ticket/9087, and neither are the
    RTS library stripped, since they don't go through Cabal).

  * never strip the copy of a library in the build directory. Only
    strip the copy that is installed. Note that Cabal never strips
    executables in the build directory either.

    This might speed up compilation of a package under development,
    since stripping won't be performed for every 'cabal build'. It is
    also consistent with the GNU coding standards for 'install-strip':

      "install-strip should not strip the executables in the build
      directory which are being copied for installation. It should only
      strip the copies that are installed."

    Source:
    http://www.gnu.org/prep/standards/html_node/Standard-Targets.html

When running the `strip` command (without the -D option) on an installed
.a file, `strip` will write the current time to all file headers in the
.a file. Update the DeterministicAr test to allow this.

The DeterministicAr test is supposed to test for regressions in
relinking avoidance. It is sufficient to do so in the build directory
only.

Remove dead code

Only the NoComments case of IncludeComments was ever used and we can
simplify the generation of the default "package environment file"
accordingly.

For ghc >= 7.10 use displayException in topHandler

(Ideally this would check the version of base instead, but that's not really
possible with bootstrapping Cabal; checking the version of ghc instead is what
happens in lots of other places so sticking with that for now.)

Warn if 'license-file' is absolute or outside of source tree (fixes #2742)

Resolve #2593: Lift global database restrictions

Eliminate InstalledPackageInfo module name parameter.

This parameter was a legacy when GHC depended directly on
Cabal; this is no longer the case so there is no need for
this parameter (which is unused inside Cabal.)

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Only include dynlink opts when building a dynamic executable

This parameter was a legacy when GHC depended directly on
Cabal; this is no longer the case so there is no need for
this parameter (which is unused inside Cabal.)

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Fixes #2766

Update documentation for test-only packages

Disable HPC in REPL for GHC

GHC doesn't support HPC in interpreter, see
https://downloads.haskell.org/~ghc/7.10.2/docs/html/users_guide/hpc.html#idp22264416

Fixes #2757

Fix deadlock in detailed-0.9 test suites

Fixes #2489. The detailed-0.9 test suite runner would deadlock because
the IO manager was not draining the output pipe of the child
process. Thanks to @r0ml for the patch.

This reverts commit f5020d41, reversing
changes made to 8d1cc528.

Fix windows build

Add frameworks when linking a dynamic library

This fixes the Cabal side of [GHC trac #10568](https://ghc.haskell.org/trac/ghc/ticket/10568)

Rename a bunch of functions of type 'Foo -> String' from 'debugFoo' to
'showFoo'.

Improve error message for unsatisfiable package constraints (issue #2643)

This commit adds the sources of constraints to debugging and error messages,
e.g., "main config file" or "command line flag".

Refactoring installplan

Support haddock response files

This change is for adding the ehancement to support haddock
response files.  This is what was used to build HP 7.10.2
for Windows, but it does need a corresponding change in
haddock to utilize it. Hopefully, this and its corresponding
haddock change can make it into the next ghc release and
eliminate much gnashing of teeth, error prone, and time
consuming manual steps in the HP build process.

Modified:

* Cabal/Distribution/Simple/Haddock.hs
  * renderArgs function: I put a couple of things into locals
    since I needed another use for UTF8 support check, plus I
    added another check based on version; the temp file logic
    was just as the prologue case above but I did need to
    repeat the invocation of the 'k' function in order to
    keep the cases separate and allow proper handling of the
    temp file automatic (or not, per --keep-temp-files)
    deletion.  Important: the haddock version being check
    against for response file support, greater than 2.16.1,
    is a placeholder and may or may not be the actual value
    since that will depend on the as-yet-unreleased haddock
    (which looks like it may be >2.16.1 but at this moment is
    not released).