examples: Extend the hello-sh example.

examples: Extend the hello-sh example.

* gettext-tools/examples/hello-sh/hello-1.sh: Renamed from
gettext-tools/examples/hello-sh/hello.sh.
* gettext-tools/examples/hello-sh/hello-2.sh: New file, based on
gettext-tools/examples/hello-sh/hello-1.sh.
* gettext-tools/examples/hello-sh/hello-3.sh: New file, based on
gettext-tools/examples/hello-sh/hello-2.sh.
* gettext-tools/examples/hello-sh/configure.ac: Update AC_CONFIG_SRCDIR
invocation and AC_CONFIG_FILES invocations.
* gettext-tools/examples/hello-sh/Makefile.am (bin_SCRIPTS): Remove hello.
Add hello-1, hello-2, hello-3.
* gettext-tools/examples/hello-sh/po/Makefile.am (POTFILES): Remove hello.sh.
Add hello-1.sh, hello-2.sh, hello-3.sh.
* gettext-tools/examples/po/Makefile.am (POTFILES): Update accordingly.
* gettext-tools/examples/Makefile.am (EXAMPLESFILES): Update file list.