The refactoring made for parsing "-L" option recently to support
"git log -L" seems to have broken "git blame -L X,-5" to show 5
lines leading to X.
* es/blame-L-breakage:
blame-options.txt: explain that -L <start> and <end> are optional
blame-options.txt: place each -L option variation on its own line
t8001/t8002 (blame): add blame -L :funcname tests
t8001/t8002 (blame): add blame -L tests
t8001/t8002 (blame): modernize style
line-range: fix "blame -L X,-N" regression