Support link to specific line number on Bitbucket

[ghost]

Links to specific line number on Bitbucket repository are not working, so I fixed.

Here's a sample build command:

$ java -jar apexdoc.jar -s 'src/classes' -g 'https://bitbucket.org/user_name/repository_name/src/master/src/classes/'

#Sorry, I'm not good at English.