bootstrap: check for git checkout correctly.

* gl/bulid-aux/bootstrap.in (func_require_git): Use .git instead
of .gitignore to recognise a git checkout.
* bootstrap: Regenerate.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
libtool: opt_duplicate_compiler_generated_deps is harmful on Solaris

Fix for http://debbugs.gnu.org/cgi/bugreport.cgi?bug=16452.
* build-aux/ltmain.in (libtool_validate_options): disable the
opt_duplicate_compiler_generated_deps optimization for Solaris2 so
that gcc-4.9+ compiled C++ code with -Wl,-Bdirect on 64-bit Solaris
x86 can avoid unwinding failures caused by accidental mixing of the
libc and libgcc_s unwinders in a single executable.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
bootstrap: use `-d .git` to check whether we are in a git tree.

* gl/build-aux/bootstrap.in (func_require_git): .git is not a
regular file, use -d to check its existence.
* bootstrap: Regenerate.
* THANKS: Add Bruce Korb.
Reported by Bruce Korb

Copyright-paperwork-exempt: Yes
Signed-off-by: Gary V. Vaughan <gary@gnu.org>
bootstrap: check for git tree with .git/. in case of soft links.

* gl/build-aux/bootstrap.in (func_require_git): Use
`test -d .git/.` to defeat soft-links versus non-GNU test.
* bootstrap: Regenerate.
* THANKS: Remove duplicate Bruce Korb entry.

Copyright-paperwork-exempt: Yes
Signed-off-by: Gary V. Vaughan <gary@gnu.org>
doc: remove redundant "in order to" phrase where possible.

* doc/libtool.texi: Remove many occurrences of the redundant
phrase "in order to", where ever "to" is as clear or clearer.
* THANKS: Add attribution.
Reported by Dave Yost

Signed-off-by: Gary V. Vaughan <gary@gnu.org>