[impl] change file browser "bookmarks" positioning

so, dig the new file browser. unfortunately i’m not digging the way that the fixed locations are at the top edge (root, /media, home, renoise library) and the 4 bookmark buttons are at the bottom. would be a lot nicer to have those directly abutting the fixed bookmarks. i generally find myself switching the file type i’m looking for (for example, clicking “sample”) and then having to move my mouse down to the bottom of the screen to select a bookmark, then back up to the folder list to navigate to where i want to go. really starting to bug me.

Definitely +1.