Workaround a bug affecting webkit on android 4.1/4.2

We need overwrite the definition in sugar-web/graphics/css/sugar.css
This bug affect us, because we need resize the matrix canvas
according to the space available.

There are more information here:
https://code.google.com/p/android/issues/detail?id=41312
I have tested every proposed workaround, and this is the only who works.
Fix toolbar position
Don't break svg reading if there non latin characters

Trying to do btoa in the svg for "minus" block,
give a error: "Uncaught InvalidCharacterError:
Failed to execute 'btoa' on 'Window': The string to be encoded
contains characters outside of the Latin1 range"
Escape the svgs before doing btoa.
Merge pull request #13 from godiard/android_fixes3

Android fixes3