templates-default: factor out definition of changeset labels This is redundant for normal and debug mode and prepares extension of this list that should effect both modes.

cmdutil: add support for evolution "troubles" display in changeset_printer Add a "trouble" line in changeset header along with a couple of labels on "log.changeset" line to indicate whether a changeset is troubled or not and which kind trouble occurs.

cmdutil: extract a _changesetlabels function out of changeset_printer._show() There is a common logic in changeset_printer and in the summary command for labelling a changeset. This prepares extension of changeset's labels with evolution "troubles" information that would show up in both log and summary outputs. Ultimately, both would use this function.

chg: add procutil.h This patch adds a formal header procutil.h for procutil.c, and changes Makefile to build procutil.c independently.

chg: let procutil maintain its own pagerpid Previously, chg.c maintains the pagerpid. Let's move it to procutil.c. Note: chg.c still have a pagerpid to decide whether to call attachio or not. In the future, attachio may be moved from hgc_open to hgc_runcommand, and hgc_runcommand handles both pager and attachio so we don't need to run attachio twice. And chg.c will be free of pagerpid.

chg: decouple hgclient from setuppager procutil should not depend on hgclient. This patch makes the pager handling part independent from hgclient.

chg: decouple hgclient from setupsignalhandler procutil should not depend on hgclient. This patch makes the signal handling part independent from hgclient.