1. add carousel start - does nothnig. ignore. copy of toolbar atm to start with

1. add carousel start - does nothnig. ignore. copy of toolbar atm to start with
2. make elementary be able to determine theme from
  PREFIX/share/elementary/themes or ~/.elementary/themes (~/ takes preference)
  currently using a delimited list of theme names in order to check like:
    mytheme/fallback/morestuff/default
  (if the last theme entry is on default it is added explicitly).
  this allows multiple theme files bascially to work a bit like a fontset - try
  the first one - if not there, try the next and so on. set $ELM_THEME to your
  theme setting
3. determine prefix and thus data dir - where system themes go. if it can't
  rely on dladdr, or the compiled-in prefix/data dir, you can set $ELM_PREFIX
  and/or $ELM_DATA_DIR accordingly.

SVN revision: 38568