Add RSpec
Convert local files shunit tests to RSpec specs
Begin testing remote files with RSpec
Check stderr first; if stdout doesn't match there is probably an error
Convert repository cloning tests to RSpec
Add "cloning" describe block to RSpec
Convert tests related to building remote shell files to RSpec
Convert remote source vs. local warning test to RSpec
Convert regression test to RSpec

This test originally covered #86.
Remove unnecessary directory existence check
Use doc format when running specs with make
Convert main --ref test
Use `touch` test helper where possible
Convert --ref missing file test
Convert tests dealing with --ref and --ignore-missing
Convert tests dealing with ignoring subdirectories when globbing
Convert tests dealing with ignoring hidden files when globbing
Use touch test helper where possible
Convert fresh order tests
Add contexts for upcoming specs