Improve make help and typo fixes in Makefile

The make help rule now has a summary of each rule so that one need not
check the Makefile every time. Of course for more details they still
have to but it's helpful for those who know what they need to do but
still might not remember all the rule names (as there are quite a few).

Typo fixes include things like incorrect statements (in comments) of
what a rule does, some being yank paste errors.

Makefile

@@ -258,33 +258,33 @@ indent.c:
 # here!
 #
 help:
-	@echo make genpath
+	@echo "make genpath - form top level .top, YYYY level .year and winner .path files"
-	@echo make genfilelist
+	@echo "make genfilelist - generate YYYY level .filelist"
-	@echo make verify_entry_files
+	@echo "make verify_entry_files - check to be sure all files in all entries exist"
-	@echo make sort_gitignore
+	@echo "make sort_gitignore - sort .gitignore files according to rules in bin/sgi.sh"
-	@echo make gen_authors
+	@echo "make gen_authors - generate the top level authors.html page"
-	@echo make gen_location
+	@echo "make gen_location - generate the top level location.html page"
-	@echo make gen_years
+	@echo "make gen_years - generate the top level years.html page"
-	@echo make entry_index
+	@echo "make entry_index - force the build of ALL winner index.html files"
-	@echo make gen_other_html
+	@echo "make gen_other_html - build entry HTML files from markdown other than README.md"
-	@echo make gen_year_index
+	@echo "make gen_year_index - generate year level index.html files using the"
-	@echo make gen_status
+	@echo "make gen_status - generate status.json and status.html"
-	@echo make gen_top_html
+	@echo "make gen_top_html - generate a number of the top level HTML files from markdown"
-	@echo make quick_entry_index
+	@echo "make quick_entry_index - build winner index.html files that might be out of date"
-	@echo make quick_www
+	@echo "make quick_www - generate html files morem quickly, checking timestamps"
-	@echo make www
+	@echo "make www - build html pages for website"
 	@echo
-	@echo make untar_entry_tarball
+	@echo "make untar_entry_tarball - untar all entry tarballs"
-	@echo make untar_year_tarball
+	@echo "make untar_year_tarball - untar all year level tarballs"
 	@echo
-	@echo make form_entry_tarball
+	@echo "make form_entry_tarball - form all entry compressed tarballs"
-	@echo make form_year_tarball
+	@echo "make form_year_tarball - form all IOCCC year level compressed tarballs"
-	@echo make tar
+	@echo "make tar - build all tarballs"
 	@echo
-	@echo make gen_sitemap
+	@echo "make gen_sitemap - generate the XML sitemap"
-	@echo make timestamp
+	@echo "make timestamp - generate things with timestamps (status, sitemap etc.)"
 	@echo
-	@echo make update
+	@echo "make update - update everything on the web site"
 
 # form the top level .top, YYYY level .year and winner level .path files
 #
@@ -335,7 +335,7 @@ verify_entry_files: ${ALL_RUN} ${CHK_ENTRY}
 	@echo '=-=-=-=-= IOCCC begin make $@ =-=-=-=-='
 	${ALL_RUN} -v 3 ${CHK_ENTRY}
 
-# check to be sure all files in all entries exist
+# sort .gitignore files according to rules in bin/sgi.sh
 #
 sort_gitignore: ${ALL_RUN} ${SORT_GITIGNORE}
 	@echo '=-=-=-=-= IOCCC begin make $@ =-=-=-=-='
@@ -388,7 +388,7 @@ thanks: ${GEN_TOP_HTML} thanks-for-help.md
 	@${GEN_TOP_HTML}
 	@echo "... and thanks for all the fish :-)"
 
-# generate build entry HTML files from markdown other than README.md to index.html HTML files
+# build entry HTML files from markdown other than README.md to index.html
 #
 gen_other_html: ${GEN_OTHER_HTML}
 	@echo '=-=-=-=-= IOCCC begin make $@ =-=-=-=-='
@@ -471,7 +471,7 @@ untar_entry_tarball: ${ALL_RUN}
 	${MAKE} verify_entry_files
 	@echo '=-=-=-=-= IOCCC complete make $@ =-=-=-=-='
 
-# untar all entry tarballs
+# untar all year level tarballs
 #
 untar_year_tarball: ${ALL_RUN}
 	@echo '=-=-=-=-= IOCCC begin make $@ =-=-=-=-='
@@ -505,7 +505,7 @@ tar:
 	${MAKE} form_year_tarball
 	@echo '=-=-=-=-= IOCCC complete make $@ =-=-=-=-='
 
-# generate a status.json and status.html
+# generate status.json and status.html
 #
 gen_status: ${GEN_STATUS}
 	@echo '=-=-=-=-= IOCCC begin make $@ =-=-=-=-='