reindenting a region does move whole region to correct level, lp:1093026

when boolean `py-tab-indents-region-p' is `t',
TAB will indent/cycle the region, not just the current line.
PyEdit, command oriented menu added
new comment-related commands:

py-uncomment 

py-comment-block, py-comment-clause,
py-comment-block-or-clause, py-comment-def,
py-comment-class, py-comment-def-or-class,
py-comment-statement