Rename solr_jvm_args to solr_jvm_opts

According to the `java` help page these are the JVM options, not the
arguments. The arguments are what is passed to the program being run.
Merge pull request #262 from basho/refactor/rz/jvm-opts

Rename solr_jvm_args to solr_jvm_opts
yz_security: update how security is enabled to match pb_security
Merge pull request #264 from basho/jrw-yz-security-enable-fix

yz_security: update how security is enabled to match pb_security
Alphabetize private functions
Add specs and private doc headers
Refuse to start if java executable cannot be found

If the `java` executable cannot be found on the PATH then exit the
initialization process.
Add logging call

There appears to be some kind of race between shutdown and the stop
reason being logged. I added this additional logging call to make sure
the reason for shutdown is logged.
Merge pull request #265 from basho/refactor/rz/no-java-shutdown

Shutdown if java cannot be found on PATH
Add create_bucket_type to yz_rt
Use more common index setup

The most common index setup is to have one bucket type, like `data`,
with each bucket underneath it pointing to its own index. Use this
style in the essential test to avoid oddities like using buckets named
`b1`.

Remove the siblings index creation as it is no longer used in this
test.
Periodically check and remove indexes for non-owned data

At some point this check was lost. There were no test failures
because all queries have node filtering which prevent these orphaned
indexes from being detected.

This patch reestablishes the check and adds a test to prevent future
regressions.
Use a proper bucket when creating object

The `Bucket` variable must now be a `{Type, Bucket}` tuple.
Merge pull request #268 from basho/bugfix/rz/bb-driver-fixes

Use a proper bucket when creating object
Merge pull request #267 from basho/bugfix/rz/remove-non-owned-data

Reestablish check to remove indexes for non-owned data
Add per-node filter queries

Create a custom SearchComponent which allows Yokozuna to perform
per-node filter queries. This removes the need for the `_yz_node` field
and the use of a monolithic filter query. Allowing smaller index size
and less overhead per query.

One microbenchmark showed a 15% increase in query throughput.
Remove unused function
Remove _yz_node field

With the addition of the per-node filter queries there is no longer a
need for the `_yz_node` field.
Fix comment for `_yz_err` field
Type & name refactoring around coverage functions

* Add some types.

* Give, arguably, better names to some functions.