Fix LDIF contination to single elided space

RFC 2849 http://tools.ietf.org/html/rfc2849:

SPACE                    = %x20
                           ; ASCII SP, space
...

2)  Any non-empty line, including comment lines, in an LDIF file
    MAY be folded by inserting a line separator (SEP) and a SPACE.
    Folding MUST NOT occur before the first character of the line.
    In other words, folding a line into two lines, the first of
    which is empty, is not permitted. Any line that begins with a
    single space MUST be treated as a continuation of the previous
    (non-empty) line. When joining folded lines, exactly one space
    character at the beginning of each continued line must be
    discarded. Implementations SHOULD NOT fold lines in the middle
    of a multi-byte UTF-8 character.

Author: mcarpenter

lib/net/ldap/dataset.rb

@@ -117,8 +117,8 @@ def read_ldif(io)
       while line
         new_line = io.gets
 
-        if new_line =~ /^[\s]+/
-          line << " " << $'
+        if new_line =~ /^ /
+          line << $'
         else
           nextline = new_line
 

test/test_ldif.rb

@@ -31,8 +31,15 @@ def test_ldif_with_password
   end
 
   def test_ldif_with_continuation_lines
-    ds = Net::LDAP::Dataset::read_ldif(StringIO.new("dn: abcdefg\r\n   hijklmn\r\n\r\n"))
-    assert_equal(true, ds.has_key?("abcdefg hijklmn"))
+    ds = Net::LDAP::Dataset::read_ldif(StringIO.new("dn: abcdefg\r\n hijklmn\r\n\r\n"))
+    assert_equal(true, ds.has_key?("abcdefghijklmn"))
+  end
+
+  def test_ldif_with_continuation_lines_and_extra_whitespace
+    ds1 = Net::LDAP::Dataset::read_ldif(StringIO.new("dn: abcdefg\r\n   hijklmn\r\n\r\n"))
+    assert_equal(true, ds1.has_key?("abcdefg  hijklmn"))
+    ds2 = Net::LDAP::Dataset::read_ldif(StringIO.new("dn: abcdefg\r\n hij  klmn\r\n\r\n"))
+    assert_equal(true, ds2.has_key?("abcdefghij  klmn"))
   end
 
   # TODO, INADEQUATE. We need some more tests