Bugfix in get_current_sequence_number()

[carldenis]

get_current_sequence_number() returns an invalid valid value if there is a file for which #{@core_file_name} ends with a digit and a second one being a prefix of the first.

For two log files named /my/path/file42.log and /my/path/file.log we will first create a /my/path/file42000001.log /my/path/file000001.log and later return 42000001 as the current maximum sequence number for file.log .

makeNewFilename will fail on line 137 with negative argument exception
padded_seq_no = "0" * (6 - @current_sequence_number.to_s.length) + @current_sequence_number.to_s

Thus, the regex is get_current_sequence_number() should be replaced with the more restrictive one from purge_log_files().

diff --git a/lib/log4r/outputter/rollingfileoutputter.rb b/lib/log4r/outputter/rollingfileoutputter.rb
index d8ecf0c..4cdd071 100644
--- a/lib/log4r/outputter/rollingfileoutputter.rb
+++ b/lib/log4r/outputter/rollingfileoutputter.rb
@@ -111,7 +111,7 @@ module Log4r
     def get_current_sequence_number()
       max_seq_no = 0
       Dir.foreach(@log_dir) do |child|
-        if child =~ /^#{@core_file_name}(\d+)#{@file_extension}$/
+        if child =~ /^#{@core_file_name}([0-9][0-9][0-9][0-9][0-9][0-9])#{@file_extension}$/
           seq_no = $1.to_i
           if (seq_no > max_seq_no)
             max_seq_no = seq_no