Update slice syntax in code writer
Update slice syntax in code writer

jessevdk/vala,playya/vala,severinh/vala,GNOME/vala,jessevdk/vala,spidermonkdust/vala,kamanashisroy/aroop,frida/vala,frida/vala,Jc2k/vala,tjol/vala-tjol,frida/vala,tjol/vala-tjol,xdave/pvala,GNOME/vala,rvu95/vala,phako/vala,flobrosch/vala-fixes,flobrosch/vala-fixes,themiwi/vala,severinh/vala,Jc2k/vala,playya/vala,GNOME/vala,themiwi/vala,Distrotech/vala,spidermonkdust/vala,rvu95/vala,playya/vala,kamanashisroy/aroop,Distrotech/vala,frida/vala,frida/vala,jessevdk/vala,Distrotech/vala,kamanashisroy/aroop,GNOME/vala,phako/vala,spidermonkdust/vala,rvu95/vala,flobrosch/vala-fixes,severinh/vala,themiwi/vala,tjol/vala-tjol