BF - remove unused log_level, make error_level functional
BF - quaternion fill threshold was not adjusted for float32 data
TEST - add tests for logging and error level; rename logger
DOC - more examples in docstring
Merge branch 'log-error-fixes' into main-master

* log-error-fixes:
  TEST - add tests for logging and error level; rename logger
  BF - remove unused log_level, make error_level functional
BF: parrec2nii does not fail immediately if one conversions fails. closes gh-30

Instead it keeps processing files and collects errors. At the end it
will dump all exceptions and fail with non-zero exit code.
Merge remote branch 'nipy/master'
BF+TEST - fix and extend trackvis scalar, property checks on write
Relax dep in Python version due to 'except Exception as ...'

Thanks Matthew for pointing it out.

Also send error messages to stderr.
RF+TEST - make tests for present data explicit - thanks to Marc-Alexandre Cote
RF - clean up most python2.6 -3 warnings
RF - further python 3 compatibility changes
BF - use passed build_py command correctly
BF - python 3 needs explicit string for configparser
RF - clean tabs from dicomwrappers
RF - removed parametric testing patch, some test cleanup
RF - attempting to deal with string vs byte for python 3
RF+BF - trying to get strings, bytes, logs working
BF - further python 3k fixes
RF - updated netcdf file from scipy distribution, adding py3k port stuff