Add in better debugging tools for understanding why a bottle is not relocatable

* When Homebrew developer mode is enabled, if a bottle is not found to be relocatable attempt to explain why
  * Print out paths of each file that still contains the string search for
  * If the string searched for was found in an executable, check to see if `otool` can explain the string's appearance
  * If otool can't explain, see if `strings` can explain