Fix bad merge with crew

Move patch-related code into its own module.

Teach import to understand git diff extensions. Vanilla patch chokes on git patches that include files that are copied or renamed, then modified. So this code detects that case and rewrites the patch if necessary.

update copyrights.

merge.

Fix some bugs introduced during the manifest refactoring

Fix "hg qnew -f foo" without -m The refresh method assumes it has a string.

merge with mpm.

Remove manifest.readflags

Change remaining users of manifest flags

Switch to simpler manifestdict

Merge: use single objects for tracking manifests

Merge: save away mode bit so that we don't need manifest later

Merge manifest refactor work

Combine manifest dict and flags dict into a single object This gets rid of the need to track two objects and might save memory. This might be faster implemented as a subclassed dict with auxiliary functions to access a sparse flags dict.