[PATCH 2 of 2] style: vertically align comment bubble icon

[Thomas De Schampheleire]

# HG changeset patch
# User Thomas De Schampheleire <thomas.de_schampheleire at nokia.com>
# Date 1537124706 -7200
#      Sun Sep 16 21:05:06 2018 +0200
# Node ID 6c3b093302ce9ef9f00ace11bc266dfabe456d85
# Parent  8b3421dac90c2efc869ec7295a3cd2b544a245d6
style: vertically align comment bubble icon

The icon of the comment bubble is slightly off-center vertically (too low).
This problem can be solved by reducing the line height.

diff --git a/kallithea/public/less/kallithea-diff.less b/kallithea/public/less/kallithea-diff.less
--- a/kallithea/public/less/kallithea-diff.less
+++ b/kallithea/public/less/kallithea-diff.less
@@ -183,6 +183,7 @@ BIN_FILENODE = 6
   background: @kallithea-theme-main-color;
   width: 16px;
   height: 16px;
+  line-height: 14px;
   cursor: pointer;
   padding: 0 2px 2px 0.5px;
   border: 1px solid @kallithea-theme-main-color;