Switch to and vendor Go Mono font

Go Mono is almost identical to Luxi Mono (same designers) but
MIT-licensed.

From https://go.googlesource.com/image font/gofont/ttfs.

1 files changed, 36 insertions, 0 deletions

diff --git a/etc/README.Go-Mono b/etc/README.Go-Mono
new file mode 100644
index 00000000..7043c362
--- /dev/null
+++ b/etc/README.Go-Mono
@@ -0,0 +1,36 @@
+These fonts were created by the Bigelow & Holmes foundry specifically for the
+Go project. See https://blog.golang.org/go-fonts for details.
+
+They are licensed under the same open source license as the rest of the Go
+project's software:
+
+Copyright (c) 2016 Bigelow & Holmes Inc.. All rights reserved.
+
+Distribution of this font is governed by the following license. If you do not
+agree to this license, including the disclaimer, do not distribute or modify
+this font.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+	* Redistributions of source code must retain the above copyright notice,
+	  this list of conditions and the following disclaimer.
+
+	* Redistributions in binary form must reproduce the above copyright notice,
+	  this list of conditions and the following disclaimer in the documentation
+	  and/or other materials provided with the distribution.
+
+	* Neither the name of Google Inc. nor the names of its contributors may be
+	  used to endorse or promote products derived from this software without
+	  specific prior written permission.
+
+DISCLAIMER: THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.