ReleaseNotes: Also show 'current' version for "Changes Since" titles

The Git for Windows Release Notes show the "Changes Since" title lines
but don't tell the user which current version they refer to.

Convert "Changes since" to:
"Changes in <version> (<small>since <previous_version></small>).

the 'snapshot' code is moved earlier, to be used in the above change line.

Note that older version had a 'preview' suffix,
e.g. v2.3.5-preview20150402, which is currently retained.

Helped-by: Johannes Schindelin <[email protected]>
Signed-off-by: Philip Oakley <[email protected]>

Author: PhilipOakley

render-release-notes.sh

@@ -105,6 +105,13 @@ render_release_notes () {
 			if ((/^<h2>Changes since (Git for Windows ([^ <]*)|(Win)?Git-([^ <]*))/)) {
 				$previous_version = $2 ? $2 : "v$4";
 
+				if ($v eq $previous_version) {
+					# in-between version
+					$v = "snapshot"
+				}
+
+				s/^<h2>Changes since(.*)/<h2>Changes in $v <small>since \1<\/small>/;
+
 				if (!$latest) {
 					s/>[^<]*/><a name="latest"$&<\/a>/;
 					$latest = 1;
@@ -116,10 +123,7 @@ render_release_notes () {
 				$nr = 0 if (!$nr);
 				$nr++;
 				$id = $v;
-				if ($v eq $previous_version) {
-					# in-between version
-					$id = "snapshot"
-				}
+
 				s/^<h2>/<h2 id="$id" nr="$nr" class="collapsible"> /;
 				$v = $previous_version;
 				s/.*/<\/div>$&<div>/;