package.json and changelog updates for release 0.7.8
Merge pull request #834 from christav/release-0.7.8

package.json and changelog updates for release 0.7.8
Merge pull request #835 from WindowsAzure/release-0.7.8

Merge release 0.7.8 to master
Merge pull request #836 from WindowsAzure/master

Merge release 0.7.8 from master to dev
Updated sas generation
Updated recordings for sas change
Merge pull request #840 from christav/fix-sas-signature-657

Add sas version into SAS calculations