Use custom vimrc in tests

[DestyNova]

• Use custom vimrc when running tests, so the results aren't determined by the user's personal vim config
  • Some of the tests fail, so I might not have the right settings in base.rc
• Make indenter test script count passes and failures at the end
• Add test result files to .gitignore
• Add testcase for multiline if/then/else (fails)