Merge pull request #21 from obarbeau/master

Use of TTF fonts
bumped up version
Update README.md
added support for reference tags
Merge branch 'master' of https://github.com/yogthos/clj-pdf
improved error message for reference tags
readme cleanup
updated to cache image and chart objects
added caching for svg elements
updated docs
changed Objects/hashCode to .hashCode to be compatible with older version of Java
Update README.md
updated to not look for system fonts by default
bumped project version
Merge branch 'master' of https://github.com/yogthos/clj-pdf

Conflicts:
	README.md
added support for setting background on chunks
added another chunk example
added the option to set multiple font styles
bumped up project version
removed unused key in paragraph