Use Chef 'platform_family' to support more linux distros

Using  `node["platform_family"]` as per
http://docs.chef.io/dsl_recipe.html#platform-family
will result in support of more linux distros that are rhel and debian based
with a very minor change.

There is a possible issue for Amazon Linux where the `tcl-devel` and `tk-devel` may not install unless yum_epel has been enabled. Even if  it is enabled, there is a chance that there could be a package conflict with the Amazon Linux repository, depending on package dependencies. 

Due to issue above, I would defer to your preference as the package maintainer to deny this PR. Thanks for taking a look! -angel