carp checkers: add carp checker and make it work

Pond.package/CarpCheckParser.class/instance/parse..st

@@ -0,0 +1,7 @@
+parsing
+parse: aStream
+	| split contents |
+	contents := aStream upToEnd.
+	contents ifEmpty: [ ^ OrderedCollection new ].
+	split := contents splitOn: '\n'.
+	^ split collect: [ :s | self parseLine: s ]

Pond.package/CarpCheckParser.class/instance/parseLine..st

@@ -0,0 +1,13 @@
+parsing
+parseLine: aLine
+	| split res |
+	split := aLine splitOn: ':'.
+	split size == 3 ifFalse: [ 
+		^ CarpParseError new message: 'unparseable checker line: "' , aLine , '"'].
+	res := CarpParseError new
+		  file: (split at: 1);
+		  line: (split at: 2) asNumber.
+	split := (split at: 3) splitOn: ' '.
+	^ res
+		  column: (split at: 1) asNumber;
+		  message: (' ' join: split allButFirst)