Add possibility to pass a cover as html
add documentation
added a newline before the return statement
Missing variable
Merge pull request #130 from krispypen/cover_as_html

Add possibility to pass a cover as html
Merge pull request #131 from aRn0D/constructor

Allowing the possibility to specify env properties for PDF and Image classes
Merge branch 'master' of https://github.com/KnpLabs/snappy