Replace hardwired strings at many places with new macros from config.h
and use the new strusage macro replacement feature.
* common/asshelp.c (lock_spawning) [W32]: Change the names of the spawn
sentinels.
* agent/command.c (cmd_import_key): Use asprintf to create the prompt.
sufficient to turn the feature on. (http_open): From here.
(http_document): And here.
* gpgkeys_hkp.c (srv_replace): New function to transform a SRV
hostname to a real hostname. (main): Call it from here for the
HAVE_LIBCURL case (without libcurl is handled via the curl-shim).
* curl-shim.h, curl-shim.c (curl_easy_setopt, curl_easy_perform): Add
a CURLOPT_SRVTAG_GPG_HACK (passed through the the http engine).
* curl-shim.h (curl_version): No need to provide a version for
curl-shim as it always matches the GnuPG version.
* gpgkeys_curl.c, gpgkeys_hkp.c (main): Show which version of curl
we're using as part of --version.
* gpgkeys_curl.c, gpgkeys_finger.c, gpgkeys_hkp.c, gpgkeys_ldap.c
(show_help): Document --version.
* gpgkeys_curl.c (main): Use curl_version_info to verify that the
protocol we're about to use is actually available.
* curl-shim.h, curl-shim.c (curl_free): Make into a macro.
(curl_version_info): New. Only advertises "http" for our shim, of
course.
protocols we handle. Directly pass them to curl or fake-curl and see if
an error comes back.
* curl-shim.h, curl-shim.c (handle_error), ksutil.c (curl_err_to_gpg_err):
Add support for CURLE_UNSUPPORTED_PROTOCOL in fake curl.
* Makefile.am: Don't need -DFAKE_CURL any longer since it's in config.h.
