Removed references to hybrid apps.
Merge pull request #1067 from zhouyaoji/docs_remove_hybrid_app_refs

[doc] Removed references to hybrid apps.
added note about trimmed copy()s
Merge pull request #1068 from drewfish/hist-copy

added note about trimmed copy()s
adding release notes for the sandbox-fix
Merge pull request #1069 from caridy/sandbox-fix

adding release notes for the sandbox-fix
release 0.5.8 (based on 0.5.7-45-gf1d7bff)
Update HISTORY.md

Updated for 0.5.8 Release