Thor version up, failing spec fixes, solr_sail dependecy deletion and new cli tests

The main purpose of this pull request is to update thor version.

The reason is --- my gem, diametric depends on lock_jar which has a dependency to thor 0.14.6. This makes hard to use diametric gem with recent Rails. There's a conflict.

Updating thor gem ended up in changing and adding bunch of code. I added cli tests to see thor version up doesn't harm anything. To see all tests pass, I need to fix some failing tests. One of them hardcoded submitter's local directory name. My changes guarantees initialization before the test starts and deletes temporary directory/files. Moreover, solr_sail dependency has been deleted. As far as I look at the code, gem doesn't use solr_sail at all. The name, "solr_sail," appears only in the sample quoted in README.md. The solr_sail gem has dependency to thor 0.14.6, which prevents updating thor to latest version.

Still, one test frequently fails, but not always. This failure is transitive dependency resolution. I believe the failure comes from naether or aether.

Please have a look at this pull request. If this looks ok, please release new version of gem.