cmdutil: enhance "getcommiteditor()" for specific usages in MQ This patch introduces "finishdesc" and "extramsg" arguments into "getcommiteditor()" for specific usages in MQ. "finishdesc" will be used to treat the commit message as "[mq]; patch-file-name" (default MQ commit message), if it is left as empty, instead of aborting commit process. "extramsg" will be used to show the line below: HG: Leave message empty to use default message instead of: HG: Leave message empty to abort commit

tag: use the editor gotten by "getcommiteditor()" instead of "ui.edit()" This patch also enhances "test-tag.t", because "hg tag" hasn't been explicitly tested around editor invocation and "--edit" option.

import: use "getcommiteditor()" instead of explicit editor choice This patch also enhances "test-import-bypass.t" and "test-import.t", because "hg import" hasn't been explicitly tested around editor invocation and "--edit" option. This patch explicitly tests below: - with "--bypass" (regardless of "--edit"): - not invoked, if the patch contains the commit message - not invoked, if the commit message is explicitly specified - invoked, otherwise (just adding comment) - without "--bypass": - with "--edit": - not invoked, if "--no-commit" is not specified - invoked, otherwise - without "--edit": - not invoked, if the patch contains the commit message - not invoked, if "--message" or "--logfile" is specified (just adding comment) - invoked, otherwise

graft: use "getcommiteditor()" instead of explicit editor choice This patch also enhances "test-graft.t", because "hg graft" hasn't been explicitly tested around editor invocation and "--edit" option.

amend: use "getcommiteditor()" instead of explicit editor choice This patch doesn't change any tests like as preceding patches, because editor invocation is already tested in "test-commit-amend.t".

commit: use "getcommiteditor()" instead of explicit editor choice This patch also eliminates "forceeditor" no more referred. This patch doesn't change any tests like as preceding patches, because editor invocation is already tested well.

backout: use "getcommiteditor()" instead of explicit editor choice This patch also enhances "test-backout.t", because "hg backout" hasn't been explicitly tested around editor invocation and '--edit' option.