Merge branch 'doc-pass5' into small-doc-changes

mathics/doc/documentation/1-Manual.mdoc

@@ -4,7 +4,7 @@
 \Mathics is a <url>:computer algebra
 system:https://en.wikipedia.org/wiki/Computer_algebra_system</url>. It is a free, open-source alternative to \Mathematica or the \Wolfram Language. However, \Mathics builds around and on top of the Python ecosystem of libraries and tools. So in a sense, you can think of it as a WMA front-end to the Python ecosystem of tools.
 
-\Mathics is free both as in "free beer" but also, more importantly, as in "freedom". \Mathics can be run locally. But to facilitate installation of the vast amount of software need to run this, there is a <url>:docker image available on dockerhub: https://hub.docker.com/r/mathicsorg/mathics</url>.
+\Mathics is free both as in "free beer" but also, more importantly, as in "freedom". \Mathics can be run locally. But to facilitate installation of the vast amount of software needed to run this, there is a <url>:docker image available on dockerhub: https://hub.docker.com/r/mathicsorg/mathics</url>.
 
 The programming language and built-in functions of \Mathics tries to match the \Wolfram Language, which is continually evolving changing.