Fixing release notes for upcoming 0.9.13 release
Adding latest commit to release notes
Merge pull request #1051 from deniszh/master_0.9.13_releasenotes

Fixing release notes for upcoming 0.9.13 release
Adding pytz test for check_dependencies.py

Fixing issue #1019
Adding pytz as dependency into install documentation
Merge pull request #1062 from deniszh/master_pytz

Master pytz
Adding #1026 to 0.9.13 release notes (master branch)
Merge pull request #1065 from deniszh/master_releasenotes2

Adding #1026 to 0.9.13 release notes (master branch)