Add support for removing newlines

This was tricky because of the nature of newlines. In actuality we
are removing Unix line feeds here (U+000A) because Windows carriage
returns are actually already removed by the string stripping in the
whitespace fix.

Creating the test case in Vim was difficult because I couldn't fig-
ure out how to manually enter a line feed character. In the end I
used a search and replace on a known pattern like "ALAN", replacing
it with \r. Neither entering the Unicode code point (U+000A) direc-
tly or typing an "Enter" character after ^V worked. Grrr.

tests/test_fix.py

@@ -47,3 +47,12 @@ def test_fix_duplicates():
     value = 'Kenya||Kenya'
 
     assert fix.duplicates(value) == 'Kenya'
+
+
+def test_fix_newlines():
+    '''Test fixing newlines.'''
+
+    value = '''Ken
+ya'''
+
+    assert fix.newlines(value) == 'Kenya'