Manpages, ponies and environment variables added

    Man page manual added.

    The directories for pony directories are changed
    from '/usr/share' to '/usr/share/ponysay' and '~' to '~/.ponysay'.

    Pony symlinks added: carrottop → carrot
                         goldenharvest → carrot
                         harpass → lyra
                         heartstrings → lyra
                         lulamoon → trixie
                         minuette → colgate
                         noteworthy → blues
                         perry → pokey
                         pokeypierce → pokey
                         timeturner → doctornohat
                         trixielulamoon → trixie
                         twilightvelvet → mrssparkle

    Support for truncating output on height, enabled by default under TTY.

    Environment variables added: 'PONYSAY_FULL_WIDTH',
    'PONYSAY_SHELL_LINES', 'PONYSAY_TRUNCATE_HEIGHT', 'PONYSAY_BOTTOM'.