list of available formats. Also added a few truecolor blocks to the test.

such as cucul_dither_t instead of struct cucul_dither.
  * Made cucul_buffer_t an opaque structure and implemented the two getters
    cucul_get_buffer_data() and cucul_get_buffer_size().
  * Documented all missing functions and function parameters.

* Fixed font selection through cucul_font_load().
  * Added a bigger 10x19 bold font.

* Removed ugly hooks from test/font.c.

* Documented most font functions.
  * Cleaned up cucul_render_canvas() and made it actually usable by external
    programs. Removed ugly printf() debug calls.

contain development tools that are only useful to libcaca developers.

really portable, and Visual Studio complains when they are not explicitely
    cast.

environment variables handling. Replaced that with three per-bitmap
    functions: cucul_set_bitmap_antialias(), cucul_set_bitmap_color() and
    cucul_set_bitmap_dithering().
  * Added cucul_set_bitmap_brightness() and cucul_set_bitmap_contrast()
    prototypes (but did not implement them yet).
  * Added cucul_set_bitmap_charset() to choose what characters are going
    to be used for the bitmap rendering.
  * Removed the now useless cucul_get_feature(), cucul_set_feature() etc.

parameter to do what both functions did before, and even more.

can add new exporters without changing the API.

that we have one function less.
  * Fixed coding style.
  * Removed FUCKING TABS.               ____.------.___
                           _______.----'`` ``` `` ``` ``-.
                      _.--' ` ```` ` `  ` ```  ``    ``  ``.
                  _.-'    ' ` `` ```      `` ` `'           `.  _
               .-''      ` H A H A H A `'  M A I S            \/.)
     .    . .-' /       `         `                  `      `` ||
     |`-.(``-.          `      `       `        ' `  `    ```  |\
     `.  '\```\        ``   `     V I E U X   ' ' ``  `-``    -|\\
       `/''````)       `` `          -        -   `````  ' '.' |\_)
        |`'_._`       ```      ''`  P O R C .   . ````        /
        // @) \    `   ``       ''' .              ```      '/
       /''''' |     ` \).`.'-.  ''' _    _         .`` `   '/
     .''''- `-'`.   . //   )--   '/,,',,' ,,,,''__,._`' '  /
   .'    ` `-  `   ' .'   /   ' /,;;;, ,___.---'     \ '' / \
   (`.  .'` __',`''''.--'/   ' /'-----'              | ' /  ))
    `'-'/  `'''_.---' \;;|-  '/            ,,,       | ''|`- |
      `'--'---'        |;|   /   ,,,,;;;;;;;;;;,,,,, |-' /`  |
                       |;|-'|   ,;;;;;;;;;;;;;;;; ;;;/  /|`'''
                       ''',,,''',,,,,,,,,,,,,,,'    /,,'''
                                   ''''

* Changed the line, box, ellipsis etc. prototypes so that they use an UTF-8
    string instead of a single character as their last argument.

onto the other with an optional mask.

canvas size (use cucul_init(0, 0) for the old behaviour).

* Bitmap gamma test example. Of       ,---.        /""`_,'
    course it does not work yet,        |    `\``""-;   /
    because some dirty old pig          \   /`\\     ';'
    implemented a cucul_powf()        .')   |     __   \
    function that only works         / (`  /     /(O\. _|
    with integer exponents.       .-`|  `"`      `    .-\_
                               .-'   \                  ` ;=-.
    HAHAHAHA MAIS            .'        .           ._,   / o o\
    VIEUX PORC !         .-'`            .           '-._;_._.J
                     .-'`                               `.-'` 
                 _. -`         L            '          .'
               .'           U                  '- ._.-'
             /`          C                         /
            /         y                           |
      ._   ;       J                         |    |
       )).-|                     |           |    /
      (/`.-|                \    \           /  .;
      ( (_)|                 |    \         ; .' |
       '--';                 |    `\       / /   |
            \                |      `\    /.'   /
             \               /        ;  |`\   |
              '.           .'      _.-|  |  |  |
                '-.     .-';_"---'`.__|  |  |  \
                   `'-._     ``'-.    |  \  \__\\
                        `''--.___\\   \__\\

the DOS/conio.h driver, and updated the unicode test accordingly.

good to have something to start with.