* tools/help2man, tools/x-to-1.in: New files, copied from gnulib
1af55d85d9762a679b4302d5995f05ccd883e956.
* configure.ac: Create x-to-1 and export CROSS_COMPILING.
* Makefile.am: Distribute help2man.
* src/bin/Makefile.am (SUBDIRS): New.
* src/bin/man/Makefile.am: New file.
* src/bin/man/genltl.x, src/bin/man/ltlfilt.x: New files.
* src/bin/genltl.cc: Document the RANGE in the options,
and move the bibliography to genltl.x.
* README: Document src/bin/man
* src/bin/common_output.cc, src/bin/common_output.hh: New file
with the common output code.
* src/bin/Makefile.am: Add them.
* src/bin/genltl.cc, src/bin/ltlfilt.cc: Simplify, using
argp's children parser, and calling output_formula().