Merge pull request 'pull into upstream' (#17) from hush/docs:master into master

Reviewed-on: https://git.hush.is/jahway603/hush-docs/pulls/17

advanced/creating-silent-dragon-msi-installer-for-windows-with-wixl.md

@@ -98,6 +98,11 @@ Below is a copy of the contents of the `SilentDragon-1.3.0.wxs` file Note that G
   </Product>
 </Wix>
 ```
+## Upgrade notes for new versions/releases 
+(https://www.firegiant.com/wix/tutorial/upgrades-and-modularization/)
+
+In order for new versions of the .msi to upgrade existing/older versions that may have been installed, the `Version` attribute needs to be incremented or changed to the new version and a new GUID for `Product` id needs to be generated (c8fae41c-889b-4621-b343-76491cd91b1c in above example).
+
 ## Build MSI file from WiX source file
 ```
 wixl -v SilentDragon-1.3.0.wxs

advanced/cross-compile-silent-dragon-for-windows-with-mxe.md

@@ -33,6 +33,7 @@ sudo apt-get install \
     libc6-dev-i386 \
     libgdk-pixbuf2.0-dev \
     libltdl-dev \
+    libgl-dev \
     libssl-dev \
     libtool-bin \
     libxml-parser-perl \
@@ -42,7 +43,9 @@ sudo apt-get install \
     p7zip-full \
     patch \
     perl \
-    python \
+    python3 \
+    python3-mako \
+    python3-pkg-resources \
     ruby \
     sed \
     unzip \