Permit negative integer literals in lexer
Permit negative integer literals in lexer

diku-dk/futhark,diku-dk/futhark,diku-dk/futhark,mrakgr/futhark,ihc/futhark,diku-dk/futhark,HIPERFIT/futhark,mrakgr/futhark,ihc/futhark,HIPERFIT/futhark,CulpaBS/wbBach,HIPERFIT/futhark,mrakgr/futhark,ihc/futhark,diku-dk/futhark