PEP8 cleanup

libntp/wscript:40:1: E101 indentation contains mixed spaces and tabs
libntp/wscript:40:1: W191 indentation contains tabs
libntp/wscript:41:1: E101 indentation contains mixed spaces and tabs
pylib/util.py:473:1: E302 expected 2 blank lines, found 1
pylib/util.py:489:39: W291 trailing whitespace
pylib/util.py:1059:5: E303 too many blank lines (2)
tests/pylib/test_agentx.py:94:1: W293 blank line contains whitespace
tests/pylib/test_agentx.py:1851:1: W293 blank line contains whitespace
wafhelpers/pythonize-header:30:32: E261 at least two spaces before inline comment
wscript:236:5: E265 block comment should start with '# '