The documentation and tests for "git format-patch" have been
cleaned up.
* dl/format-patch-doc-test-cleanup:
config/format.txt: specify default value of format.coverLetter
Doc: add more detail for git-format-patch
t4014: stop losing return codes of git commands
t4014: remove confusing pipe in check_threading()
t4014: use test_line_count() where possible
t4014: let sed open its own files
t4014: drop redirections to /dev/null
t4014: use indentable here-docs
t4014: remove spaces after redirect operators
t4014: use sq for test case names
t4014: move closing sq onto its own line
t4014: s/expected/expect/
t4014: drop unnecessary blank lines from test cases
1c6fc941c7