Remove redundant MarkupSafe download

Jinja2 seems to download MarkupSafe as well as Jinja2-2.7.1. Having MarkupSafe in the dependency list causes it to fail when the MarkupSafe file already exists.

Also, jinja2 should be Jinja2 as the tarball is Jinja2-2.7.1.tar.gz, not jinja2-2.7.1.tar.gz