Merge pull request #248 from bhariharan/unstable20

Merge branch 'unstable' into unstable20
Add upgrade notes from 1.4.7 to 1.5
Merge pull request #249 from bhariharan/master

Add upgrade notes from 1.4.7 to 1.5
Merge branch 'master' into unstable
Merge pull request #250 from bhariharan/unstable

Merge 'master' into unstable
Merge branch 'unstable' into unstable20