Add sunspot gems into Gemfile.  #23

Signed-off-by: ataka <masayuki.ataka@gmail.com>
Generate config/sunspot.yml  #23

by `bundle exec rails generate sunspot_rails:install` .

Signed-off-by: ataka <masayuki.ataka@gmail.com>
New feature: Search in Blog using sunspot.  close #23

Added solr/conf/*.

Index page displays all searched results with keyword ''.
You can search keyword 'foo' using query ?q=foo,
and results will be changed.

Signed-off-by: ataka <masayuki.ataka@gmail.com>
Ignore Solr data.  #23

I am unfamiliar with Solr, so these ignoration maybe not correct.

Signed-off-by: ataka <masayuki.ataka@gmail.com>