Incorporate some git information into NetHack

Incorporate some git information into NetHack so that it
is potentially visible to a player. That's useful when
collecting details about the version that they are
running and, if the gitinfo is present, it can tie the
code to a specific git commit in the repository.

This modifies 'makedefs -v' to check for the presence of a data file
called dat/gitinfo.txt and if it is there, parse out its
contents, then write additional lines to include/date.h beyond
what 'makedefs -v' was previously putting in there, similar to
this sample:

      #define NETHACK_GIT_SHA "0c84e564c78e2024e562d39539376ce2e21eec8e"
      #define NETHACK_GIT_BRANCH "NetHack-3.6.0"

The contents of an appropriate dat/gitinfo.txt are as follows,
and trailing/leading whitespace is not significant:

      githash = 0c84e564c78e2024e562d39539376ce2e21eec8e
      gitbranch = NetHack-3.6.0

It also adjusts the contents of the 'v' version information to
include the additional git info when available.

Also adds some hooks DEVEL/hooksdir and a perl file to DEVEL
for simplifying and automating the deposit of dat/gitinfo.txt
so that it generally reflects the most current git commit.

DEVEL/gitinfo.pl can be used to build dat/gitinfo.txt at any
time without doing a commit, merge, or checkout.
    	perl DEVEL/gitinfo.pl

command line --version and -version support

To complement the extra information being provided in the
version by the 'v' command, this also adds support for the
following new command line arguments:
    --version
     -version            Output the NetHack version string then exit.

    --version:paste      Output the NetHack version string and also copy it to
     -version:paste      the platform's paste buffer for insertion somewhere,
                         then exit.

If the paste variation of -version is requested on a platform that
hasn't incorporated any support for the capability, it will deliver
the version info then an error message, prior to exiting.

To support the extended -version:paste variation, a port needs to:
    - provide a port-specific routine to perform
      the paste buffer copy in a port code file.
    - #define RUNTIME_PASTEBUF_SUPPORT in the include/portconf.h header file.

    --skeleton--
    void port_insert_pastebuf(buf)
    char *buf;
    {
    	/* insert code to copy the version info from buf into
    	   platform's paste buffer in a supported way */
    }

macosx and Windows have both added support for RUNTIME_PASTEBUF_SUPPORT

sys/unix/unixmain.c

@@ -110,6 +110,9 @@ char *argv[];
         dir = nh_getenv("HACKDIR");
 
     if (argc > 1) {
+        if (argcheck(argc, argv, ARG_VERSION))
+            exit(EXIT_SUCCESS);
+
         if (!strncmp(argv[1], "-d", 2) && argv[1][2] != 'e') {
             /* avoid matching "-dec" for DECgraphics; since the man page
              * says -d directory, hope nobody's using -desomething_else
@@ -720,4 +723,40 @@ get_login_name()
     return buf;
 }
 
+#ifdef __APPLE__
+extern int errno;
+
+void
+port_insert_pastebuf(buf)
+char *buf;
+{
+    /* This should be replaced when there is a Cocoa port. */
+    const char *errfmt;
+    size_t len;
+    FILE *PB = popen("/usr/bin/pbcopy","w");
+    if(!PB){
+	errfmt = "Unable to start pbcopy (%d)\n";
+	goto error;
+    }
+
+    len = strlen(buf);
+    /* Remove the trailing \n, carefully. */
+    if(buf[len-1] == '\n') len--;
+
+    /* XXX Sorry, I'm too lazy to write a loop for output this short. */
+    if(len!=fwrite(buf,1,len,PB)){
+	errfmt = "Error sending data to pbcopy (%d)\n";
+	goto error;
+    }
+
+    if(pclose(PB)!=-1){
+	return;
+    }
+    errfmt = "Error finishing pbcopy (%d)\n";
+
+error:
+    raw_printf(errfmt,strerror(errno));
+}
+#endif
+
 /*unixmain.c*/