doc style: better @since html render

Now @since have a left colored border, like @deprecaded, @note, etc

Also keep the number on the same line:
instead of:
since
        1.10
it now render as:
since 1.10

1 files changed, 6 insertions, 2 deletions

diff --git a/doc/e.css b/doc/e.css
index f286f8c224..551f009fcd 100644
--- a/doc/e.css
+++ b/doc/e.css
@@ -783,7 +783,7 @@ dl {
   padding: 0 0 0 10px;
 }
 
-dl.note, dl.warning, dl.attention, dl.pre, dl.post, dl.invariant, dl.deprecated, dl.todo, dl.test, dl.bug {
+dl.note, dl.warning, dl.attention, dl.pre, dl.post, dl.invariant, dl.deprecated, dl.todo, dl.test, dl.bug, dl.since {
   border-left: 4px solid;
   padding: 0 0 0 6px;
 }
@@ -800,10 +800,14 @@ dl.pre, dl.post, dl.invariant {
   border-color: #00D000;
 }
 
-dl.deprecated {
+dl.deprecated, dl.since {
   border-color: #505050;
 }
 
+dl.since dt {
+  height: 0;
+}
+
 dl.todo {
   border-color: #00C0E0;
 }