fix CR-IC-97 (indent is counted in tab units so need multiplication instead of division)

handle empty insertion line properly

python/testData/copyPaste/IndentTabIncrease.after.py

@@ -0,0 +1,6 @@
+print "Line 2"
+class Test:
+	def __init__(self):
+		print "Line 2"
+
+		print "Line 1"

python/testData/copyPaste/IndentTabIncrease.dst.py

@@ -0,0 +1,5 @@
+print "Line 2"
+class Test:
+	def __init__(self):
+		<caret>
+		print "Line 1"

python/testData/copyPaste/IndentTabIncrease.src.py

@@ -0,0 +1,5 @@
+<selection>print "Line 2"
+</selection><caret>
+class Test:
+	def __init__(self):
+		print "Line 1"