add license badge icon to readme
Allow using the library externally by catching the exceptions while loading properties from unavailable classes.
handles manifests with missing named attributes.

 - fixes #512
Merge branch 'master' of github.com:teprrr/Apktool into teprrr-master
Merge branch 'teprrr-master'
[skip] remove newline at EOF
[skip] added changes note for PR #84