* relocate: removed import from statements
* relocate: renamed *Exception to *Error
This aims at consistency in naming with both
the standard library (ValueError, AttributeError,
etc.) and other errors in 'spack.error'.
Improved existing docstrings
* relocate: simplified search function by un-nesting conditionals
The search function that searches for patchelf has been
refactored to remove deeply nested conditionals.
Extended docstring.
* relocate: removed a condition specific to unit tests
* relocate: added test for _patchelf
1b4de7813a