disable menu functions of the edit menu when no files are open, added the possibility to delete an existing fifo in the case, that Geany crashed previously, replaced the New toolbar button by a menu button, so it works also under Win32


git-svn-id: https://geany.svn.sourceforge.net/svnroot/geany/trunk@208 ea778897-0a13-0410-b9d1-a72fbfd435f5