gitk: Do not depend on Cygwin's "kill" command on Windows

Windows does not necessarily mean Cygwin, it could also be MSYS. The
latter ships with a version of "kill" that does not understand "-f".
In msysgit this was addressed by shipping Cygwin's version of kill.

Properly fix this by using the stock Windows "taskkill" command instead,
which is available since Windows XP Professional.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
gitk: Show detached HEAD if --all is specified

If HEAD is detached, 'gitk --all' does not show it. This is inconvenient
for frontend program, and for example git log does show the detached HEAD.

gitk uses git rev-parse to find a list of branches to show.
Apparently, the command does not include detached HEAD to output if
--all argument is specified. This has been discussed in [1] and stated
as expected behavior. So rev-parse's parameters should be tuned in gitk.

[1] http://thread.gmane.org/gmane.comp.version-control.git/255996

Signed-off-by: Max Kirillov <max@max630.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
gitk: Remove boilerplate for configuration variables

Signed-off-by: Max Kirillov <max@max630.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Merge git://ozlabs.org/~paulus/gitk

* git://ozlabs.org/~paulus/gitk:
  gitk: Remove boilerplate for configuration variables
  gitk: Show detached HEAD if --all is specified
  gitk: Do not depend on Cygwin's "kill" command on Windows