Merge pull request #30 from SimonSapin/master

 Handle scientific notation with a capital E, fix Kozea/CairoSVG#29
Cache trees already parsed
Use pillow instead of pystacia, drop Python 3.1 support
Fix the test's README to use pillow instead of pystacia
Added space preserve functionality
Merge pull request #31 from cristen/master

Added handling of whitespaces with preserve option
Merge branch 'cristen'
Update the tests to use infinality
Merge branch 'master' of github.com:Kozea/CairoSVG
Add support for the clip property
Consider files beginning with a doctype as SVG
Add new passing test
Add support for pattern inheriting
And no follow x and y coordinates for circles
Merge branch 'master' of github.com:Kozea/CairoSVG
Typo
Add another passing test
Add support for "cascade" pattern inheriting.
Consider the parent node children when inheriting
Fix some tests and put an id to anonymous elements
Fix image in test
Fix the last failing test for patterns