tests: make directory to prevent test process from going out of $TESTTMP Before this patch, test process for test-bookmarks.t goes out of $TESTTMP at "cd .." before creation of "orderrepo" repository. To prevent test process from going out of $TESTTMP, this patch makes directory "repo" sub-directory and executes almost all test scenarios in test-bookmarks.t under it. This is preparation for new test added in subsequent patch.

txnutil: factor out the logic to read file in according to HG_PENDING This patch adds new file txnutil.py, because: - transaction.py is too large to import small utility logic - scmutil.py or so causes cyclic importing in phases.py mayhavepending() is defined separately for convenience in subsequent patch.

repoview: separate cache hash computation from cache reading This change will make it easier for extensions to use another cache hash.