merge with stable

check-code: detect legacy exception syntax We just rewrote all files to use modern exception syntax. Ban the old form. This will detect the "except type, instance" and "except (type1, type2), instance" forms.

global: mass rewrite to use modern exception syntax Python 2.6 introduced the "except type as instance" syntax, replacing the "except type, instance" syntax that came before. Python 3 dropped support for the latter syntax. Since we no longer support Python 2.4 or 2.5, we have no need to continue supporting the "except type, instance". This patch mass rewrites the exception syntax to be Python 2.6+ and Python 3 compatible. This patch was produced by running `2to3 -f except -w -n .`.

check-code: detect legacy octal syntax Now that we have mass rewriting all files to use the modern octal syntax, detect and ban the legacy syntax, which is no longer supported in Python 3.

global: mass rewrite to use modern octal syntax Python 2.6 introduced a new octal syntax: "0oXXX", replacing "0XXX". The old syntax is not recognized in Python 3 and will result in a parse error. Mass rewrite all instances of the old octal syntax to the new syntax. This patch was generated by `2to3 -f numliterals -w -n .` and the diff was selectively recorded to exclude changes to "<N>l" syntax conversion, which will be handled separately.

revert: change the direction of revert -i After the discussion on the list about hg revert -i, it seems like we are satisfied with what we called proposition 2. It shows the changes to revert in the same direction as hg diff. This patch makes it the default option. It changes all the + in - and vice versa in the tests for revert -i.