Updated README

With MySQL 5.6 default configuration is more strict and adds STRICT_TRANS_TABLES.

Added some info to configure MySQL properly. Better solution would be to make the schema correctly, defining optional columns as nullable.
One little modification on formatting
increment thelia version
Removed header titles from the pges that have one
Merge pull request #388 from roadster31/coupons

Removed header titles from the pges that have one
change downlod link on admin homepage
Merge pull request #387 from lunika/2.0.1

increment thelia version
Merge branch 'master' into doc-mysql56

Conflicts:
	Readme.md
Merge pull request #381 from moustikAir/doc-mysql56

MySQL 5.6 default config creates bug