reworks text viewer plugin. (FS#11209)

new text viewer plugin: text_viewer.rock.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@26571 a1c6a512-1295-4272-9138-f99709370657

apps/plugins/text_viewer/readme.txt

@@ -0,0 +1,62 @@
+about the text viewer plugin.
+
+Limitation
+    for the target which PLUGIN_BUFFER_SIZE < 0x13000 (i.e., archos series),
+    can only be read up to 999 pages.
+
+
+Difference between viewer.rock
+    [settings file]
+       - the global setting, 'tv_global.dat' is stored.
+       - Settings and bookmarks for each file, 'tv_file.dat' is stored.
+
+      Note: when viewer.dat(viewer_file.dat) exists, tv_global.dat(tv_file.dat) is created by
+            using viewer.dat(viewer_file.dat).
+
+    [wod wrap]
+          - add the following characters which can be split the line.
+                '!', ',', '.', ':', ';', '?', 
+                U+00b7, U+2010, U+3000, U+3001, U+3002, U+30fb, U+30fc, 
+                U+ff01, U+ff0c, U+ff0d, U+ff0e, U+ff1a, U+ff1b, U+ff1f.
+
+          - when the line split, if the line length is short ( < 0.75 * display width), 
+            split the line in display width. (thus, maybe split a word)
+
+    [line mode]
+       [join]
+           - break line condition has changed.
+               - If the next line is a blank line or spaces only line, this line breaks.
+
+       [reflow]
+           - indent changes two spaces.
+           - supports the player which does not define HAVE_LCD_BITMAP.
+
+    [alignment]
+           - the right alignment supports the player which does not define HAVE_LCD_BITMAP.
+
+    [bookmark]
+           - increased to 16 the number of bookmarks that can be registered.
+
+
+TODO list
+  - for the target which PLUGIN_BUFFER_SIZE < 0x13000 (i.e., archos series),   
+    supports more than 999 pages of text.
+
+  - add History feature.
+
+  - when the WIDE screen, allow to specify the number of screens.
+
+  - when the line_mode is reflow, allow to specify indent spaces.
+
+  - for the horizontal scroll, allow the select scroll by screen/scroll by column for the settings menu.
+
+  - can display the horizontal scroll bar.
+
+  - draw images that are linked to the text. (<img src="...">)
+
+  - play audios that are linked to the text. (<audio src="...">)
+
+  - more treatments of line breaking, word wrappings.
+    (for example, period does not appear the top of line.)
+
+  - whether scroll to prev/next page or scroll to top page/bottom page can be select the settings menu.