Updating existing NewGRF

1. be sure, if its really a update (md5sum)
2. commit to SVN with a proper message
3. Update GRF Table (Trunk)
   1. edit title with revision number
   2. check link, if its still direct to the current revision (grfcrawler isn't always right, TT-Forums should work if no official link available, links mostly change after update there...)
   3. if there is a readme available, a link from column Details would be nice (link to www.openttdcoop.org/newgrfs/...)
   4. after update, the credits might also change...
   5. write the svn revision to status

Adding new GRF

1. create a directory in the category, it belongs to. Also possible it needs an other location, because of a special dependency. Then you create a folder "a" or something like that for it, or you move it to top (1_others) or to bottom (9_last). EVERY GRF has its own directory. (svn mkdir; svn add <grf>)
2. Update GRF Table (Trunk)
   1. title with revision number
   2. link to grf, grfcrawler isn't always right, TT-Forums should work if no official link available, links mostly change after update there...
   3. if there is a readme available, a link from column Details would be nice (link to www.openttdcoop.org/newgrfs/...)
   4. don't forget the credits (you see them in the GRF itself...)
   5. write the svn revision to status

Preambles for SVN commits

Update: updating existing GRF

New: adding new GRF

Orders: moving existing GRF to better place to fix order dependencies

Fix: fixing some other bugs ;-)

Release: new tag etc.