Documentation fix

[jrs]

Just was installing cpg, and was using the documentation on the website to do it, and noticed a problem:

In the "What is required" section, you list the permissions that need to be granted to the mysql user.  It appears that you also need to be granted INSERT, which isn't listed, or running install.php fails.

Thanks for the cool program.

[Nibbler]

The documentation says:

The mySQL user needs the permissions CREATE TABLE, INSERT, ALTER, UPDATE, DELETE, SELECT.

[jrs]

It says that in 2.1.2 - The install screen.  However, 1. What is required, it states

The MySQL user needs permissions to perform CREATE, ALTER, SELECT, UPDATE, DELETE data from the database.

[Joachim Müller]

updated docs as suggested both in devel and stable branch.