[CC-763] Make it easier to install newer version of Solr

SUMMARY OF CHANGES

* [FIX] Install Solr only on the util instance named "solr". The current version installs Solr on all util instances
* [NEW] Install the latest version of Solr, 4.10.2
* [NEW] Optionally enable, install and eselect Java 7
* [NEW] Create /data/appname/shared/config/solr.yml on all app_master, app, util and solo instances


TESTS DONE

1. Boot a Gentoo 2009 solo instance, set use_default_java = true. solo instance should use system java and install solr 1.4
2. Boot a Gentoo 12.11 cluster with 2 util instances, solr and notsolr. After the chef run:

- solr instance - has Java 7, solr running, has solr.yml in /data/appname/shared/config
- notsolr - still on Java 6, no solr running, has solr.yml in /data/appname/shared/config
- app_master - still on Java 6, no solr running, has solr.yml in /data/appname/shared/config