Updated TODO

Turned out these were some really bad ideas:

 1) mapping mime to file types would need to be duplicated in frontend
    and backend
 2) even if frontend and backend could share mime type map somehow,
    frontend would have problems with including it - ajax and the like
 3) it either would be impossible to refer to user avatar by their owner
    user names in URLs, or dao layer would need to synchronize avatar
    content files when user changes his name
 4) presenters still need to decorate urls with /data/ and
    /data/thumbnails/100x100
 5) managing file extensions of thumbnails would be a real pain since it
    partially shares its path names with real content, but under
    different mime type

Generally it's best to leave it to Apache to transmit correct mime.

TODO

@@ -123,10 +123,6 @@ refactors:
       separate PostTagDao for this)
     - post view proxy should retrieve full tags and full user
     - centralize markdown prefix decorators
-    - move getPostContentPath and getAvatarSourcePath to Entity, include it in
-      ViewProxy and make presenters use it instead of duplicating the code
-    - after implementing Post::getPostContentPath, make paths include file
-      extensions so that apache can guess mime types when it serves the files
     - add enum validation in IValidatables (needs refactors of enums and
       possible disposal of EnumHelper in favor of something more subtle)
     - (idea) keep denormalized data in separate tables, i.e. tag usages in
@@ -156,6 +152,7 @@ miscellaneous:
     - endless pager should include information about page number
     - add README and INSTALL - apache2 has good README:
       http://svn.apache.org/repos/asf/httpd/httpd/trunk/README
+      remember to mention mod_mime_magic
     - add spinner to forms such as registration, user query, login, settings
       etc. make sure the code isn't too duplicated.