allow replacing the root of the document

This fixes the test from
https://github.com/json-patch/json-patch-tests/commit/4db5098183c0e1d706b4525
mention RFC 6902
require jsonpointer>=1.0
bump version to 1.0
use unicode literals and update tests
add support for Python 3.3 and PyPy
add documentation
README: add link to docs
Fixed replacing whole document
- json pointer to_last operation returns None for the part in the
  case that it is a whole document pointer
- json patch now checks to see if the part is None and simply returns
  the value to replace the document
- Added a test to verify the fix
add William Kral to AUTHORS
bump version to 1.1
rework coverage calculation for coveralls.io
add test for comparing patches to other types
remove unused parameter to JsonPointer.to_last()
exclude compatibility code from coverage calculation
test __str__() and to_string()
test some invalid inputs
don't include not implemented methods in coverage
Merge branch 'master' of github.com:stefankoegl/python-json-patch
refactor equality comparison