Update release notes and version to 0.10.0

v0.9.0 release

Bump version to 0.8 - py3 release

Merge branch 'fixup_docs'

Merge pull request dnephin#61 from dnephin/load_without_flatten

Allow for non-flattening loaders.

Resolves dnephin#49, Add log level validator.

Fix dnephin#50, proxy used as index or slice.

Fix bug with ValueProxyFactory that would cause a crash if a proxy ha…

…d a non-immutable default value.

Merge pull request dnephin#48 from dnephin/45_clear_config_on_reload

45 clear config on reload

Merge pull request dnephin#38 from dnephin/only_hold_weakref_to_proxies

0.5.2 only hold weakref to proxies.