libc/uClibc: enable NPTL for snapshots

Recently, NPTL has matured a lot in uClibc, and more and more
people are interested to at least give it a try. So enable it.

libc/uClibc: fix snapshots

Snapshots are in a subdir named uClibc, not uClibc-snapshot
(or uClibc-YYYYMMDD either).

libc/uClibc: fix munging .config for LT old/new

debug/ltrace: add latest version

scripts/finish: do not try to symlink if sed expr is a no-op

If the sed expression does not transform the
tuple, do not try to create the symlink.
(transplanted from 5d6d3c28a658a65551d4eb5de414fd97b575f314)

scripts/finish: do not try to symlink if sed expr is a no-op

If the sed expression does not transform the
tuple, do not try to create the symlink.

debug/gdb: fix incorrect path

Fix discrepancy between the directory we create,
and the directory into which we install tic.

libc/glibc: fix installed scripts

glibc installs some bash-scripts, but uses the path to the buildtool
bash as interpreter (on the shebang line). This is only a symlink to
the real bash, and thus is not available at runtime.

Fix that by assuming that bash on the target *will* be /bin/bash.

1.7: update version to 1.7.1+hg

Tagging release 1.7.1