Log Message:
Update to 1.7.3.
Bugs fixed in 1.7.3:
* Fix stamp files numbering (when using multiple AC_CONFIG_HEADERS).
* Query distutils for `pythondir' and `pythonexecdir', instead of
  using an hardcoded path.  This should allow builds on 64-bit
  distributions that usually use lib64/ instead of lib/.
* AM_PATH_PYTHON will also search for python2.3.
* elisp files are now built all at once instead of one by one. Besides
  incurring a speed-up, this is required to support interdependent elisp files.
* Fix some incompatibilities with upcoming perl-5.10.
* Properly quote AC_PACKAGE_TARNAME and AC_PACKAGE_VERSION when defining
  PACKAGE and VERSION.
* depcomp fixes:
  - dashmstdout and dashXmstdout modes: don't use `-o /dev/null', this
    is troublesome with gcc and Solaris compilers.
  - makedepend mode: work with Libtool.
  - support for ICC.
* better support for unusual gettext setups, such as multiple po/ directories:
  - Flag missing po/ and intl/ directories as warnings, not errors.
  - Disable these warnings if po/ does not exist.
* Noteworthy manual updates:
  - New FAQ chapter.
  - Document how AC_CONFIG_AUX_DIR interacts with missing files.
    (Debian Bug #39542)
  - Document `AM_YFLAGS = -d'.