Fix a few issues found by landscape.io

Lib/fontTools/agl.py

@@ -705,7 +705,8 @@ _aglText = """\
 """
 
 
-AGLError = "AGLError"
+class AGLError(Exception):
+	pass
 
 AGL2UV = {}
 UV2AGL = {}

Lib/fontTools/cffLib.py

@@ -457,6 +457,7 @@ class	FDSelect:
 			elif self.format == 3:
 				gidArray = [None] * numGlyphs
 				nRanges = readCard16(file)
+				fd = None
 				prev = None
 				for i in range(nRanges):
 					first = readCard16(file)

Lib/fontTools/merge.py

@@ -680,7 +680,7 @@ class Options(object):
 	v = a[i+1:]
       k = k.replace('-', '_')
       if not hasattr(self, k):
-	if ignore_unknown == True or k in ignore_unknown:
+	if ignore_unknown is True or k in ignore_unknown:
 	  ret.append(orig_a)
 	  continue
 	else:

Lib/fontTools/misc/psLib.py

@@ -319,7 +319,6 @@ def unpack_item(item):
 	return newitem
 
 def suckfont(data):
-	import re
 	m = re.search(br"/FontName\s+/([^ \t\n\r]+)\s+def", data)
 	if m:
 		fontName = m.group(1)