Import to 0.6.1

Import to 0.6.1
  0.5.0:
    document "trim" modifier
    add xo_emit_field functions
    Add xo_set_file{,_h} functions
    Fix LIBXO_* variables; add -L and -I as needed
    add --disable-silent-rules and an explicit make; s/PACKAGE-NAME/PACKAGE_NAME/; add /download/ to 'url'
    fix silliness where xo_flush_h emitted closing tag (html); make the caller (xo_message) do it
    flush after transitions; fix flush call in xo_do_emit
    mkdir the version-specific packaging dir
    use "XO_" instead of LIBXO_

  0.6.0:
    Add --with-retain-size to set the size (in bits) of the retain hash buckets
    Add The Argument Modifier ({a:})
    Add retain and no-retain to --libxo
    autoconf: Add test for monitor.h
    Document quote heuristic
    go deep with nroff backslashes
    Use "ULL" for 32 bit check
    add xo_retain_clear and xo_retain_clear_all
    docs: combine two 'handles' section; move command line argument section
    handle GETTEXT when msgfmt isn't where it's supposed to be (FreeBSD)
    make 'retain' a flag (XOEF_RETAIN) instead of a role; it's simpler, and doesn't feel as tacky. "{R:}" was painful to document, which means it's painful to use.
    new xo_emit_f functions
    nuke some unused UNUSEDs
    test code: path must be static
    update test cases

  0.6.1:
    fix version number (missed a commit during new-release)

Reviewed by:	sjg
Approved by:	sjg (mentor)