Automark: first release

Simple plugin that automatically highlights current word (no hotkeys or so on):

![Automark](http://i.imgur.com/q6YyuN4.png)

Now I should touch 16 files, right? (remembered that magic number)
Here the replacement would be something like this:
```C
gint pos = sci_get_current_position(editor->sci);
gint start = SSM(editor->sci, SCI_WORDSTARTPOSITION, pos, TRUE);
gint end = SSM(editor->sci, SCI_WORDENDPOSITION, pos, TRUE);
/* Bonus! word is allocated and can be any length :)
 * (otherwise if you really want manual allocation, no
 * biggie use sci_get_text_range() */
gchar *word = sci_get_contents_range(editor->sci, start, end);
```

But anyway, we generally accept adding plugin API if it is reasonable and we are asked for.