master
tidy-up: comments, messages, formatting
curlx: rename `Curl_`-prefixed symbols to `curlx_`
tidy-up: fix comment indentation
lib: use lib source directory as base include path
tidy-up: rename `Curl_safefree()`/`tool_safefree()` to `curlx_safefree()`
clang-tidy: enable more checks, fix fallouts
tidy-up: miscellaneous
build: always use local `inet_pton()`/`inet_ntop()` implementations
tidy-up: typos, comment nits
idn: restore `MultiByteToWideChar()` `MB_ERR_INVALID_CHARS` flag
build: drop duplicate include `curl/curl.h` and others
gcc: guard `#pragma diagnostic` in core code for <4.6, disable picky warnings
curlx: add local `snprintf()` helper that always nul-terminates (Windows)
curlx: curlx_strcopy() instead of strcpy()
build: enable `-Wformat-signedness`, fix issues found
curlx: move Curl_strerror, use in src and tests, ban `strerror` globally
strparse: make curlx_str_until() accept zero for 'max'
timeval: rename timer frequency variable
windows: determine `RtlVerifyVersionInfo` address on global init
build: assume POSIX `select()` is available
clang-tidy: sync argument names in prototype and definition
tool_doswin: add stdin relay auth