Merge branch 'maint-1.8.1' into maint

* maint-1.8.1:
bundle: Add colons to list headings in "verify"
bundle: Fix "verify" output if history is complete
Documentation: filter-branch env-filter example
git-filter-branch.txt: clarify ident variables usage
git-compat-util.h: Provide missing netdb.h definitions
describe: Document --match pattern format
Documentation/githooks: Explain pre-rebase parameters
update-index: list supported idx versions and their features
diff-options: unconfuse description of --color
read-cache.c: use INDEX_FORMAT_{LB,UB} in verify_hdr()
index-format.txt: mention of v4 is missing in some places

diff --cc Documentation/diff-options.txt
Simple merge

diff --cc Documentation/git-describe.txt
Simple merge

diff --cc Documentation/git-filter-branch.txt
Simple merge

diff --cc Documentation/git-update-index.txt
Simple merge

diff --cc Documentation/githooks.txt
Simple merge

diff --cc Documentation/technical/index-format.txt
Simple merge

diff --cc git-compat-util.h
Simple merge

diff --cc read-cache.c
Simple merge