correction of typos in README.md

Write only one compressed archive and fixed some problems

1.Make it python2 and python3 compatible 2.Try to solve special character when saving dashboard, folder problem 3.Add more verbose log message

Update tool to support folders

Folders are available since Grafana v.5.0.*. Create scripts to migrate
folders and dashboards (with folders id)

Dashboard replacement

A 412 failure from grafana prevents passing a dashboard with a slug that
is already present (i.e. restoring from a backup) to createDashboard.py.
Handle this by always deleting dashboards with the same name from
grafana prior to POSTing the new dashboard.

* Use the PEP 8 recommended whitespace formatting for .py files
* Add intellij files to the .gitignore file patterns

fix typo