[baseimage] set default locale en_US.UTF-8 (#1988)

* [baseimage] set default locale en_US.UTF-8

Signed-off-by: chenhu <chenhu@didichuxing.com>

* [baseimage]set default locale to en_US.UTF-8, clean all other unused

* [baseimage] update-locale after locale-gen

* correct update-locale command line

Signed-off-by: Guohan Lu <gulv@microsoft.com>

build_debian.sh

@@ -227,7 +227,14 @@ sudo LANG=C DEBIAN_FRONTEND=noninteractive chroot $FILESYSTEM_ROOT apt-get -y in
     hping3                  \
     python-scapy            \
     tcptraceroute           \
-    mtr-tiny
+    mtr-tiny                \
+    locales
+
+#Adds a locale to a debian system in non-interactive mode
+sudo sed -i '/^#.* en_US.* /s/^#//' $FILESYSTEM_ROOT/etc/locale.gen && \
+    sudo LANG=C DEBIAN_FRONTEND=noninteractive chroot $FILESYSTEM_ROOT locale-gen "en_US.UTF-8"
+sudo LANG=en_US.UTF-8 DEBIAN_FRONTEND=noninteractive chroot $FILESYSTEM_ROOT update-locale "LANG=en_US.UTF-8"
+sudo LANG=C chroot $FILESYSTEM_ROOT bash -c "find /usr/share/i18n/locales/ ! -name 'en_US' -type f -exec rm -f {} +"
 
 # Install certain fundamental packages from stretch-backports in order to get
 # more up-to-date (but potentially less stable) versions