Reflow all the language stack README-content.md files to 80 columns and incorporate Fred's changes

This also includes Fred's updates to the `README-short.txt` files, and a bunch of very minor changes for consistency (using "PHP" instead of "php", ending sentences that describe and lead into a code block with a ":", using "Go" instead of "Golang" and "Hy" instead of "Hylang" within prose, not using periods at the end of headlines, etc).

A really fun one included here is that Java mentioned both using GNU Make inside the container (and `java` doesn't include `make` presently), and some of the prose mentioned `go build` after we ran `javac`, which was extra neat.

java/README-content.md

@@ -1,6 +1,9 @@
 # What is Java?
 
-Java is a concurrent, class-based, object-oriented language specifically designed to have as few implementation dependencies as possible. It is intended to allow application developers to "write once, run anywhere", meaning that code that runs on one platform does not need to be recompiled to run on another.
+Java is a concurrent, class-based, object-oriented language specifically
+designed to have as few implementation dependencies as possible. It is intended
+to allow application developers to "write once, run anywhere", meaning that code
+that runs on one platform does not need to be recompiled to run on another.
 
 Java is a registered trademark of Oracle and/or its affiliates.
 
@@ -8,9 +11,11 @@ Java is a registered trademark of Oracle and/or its affiliates.
 
 # How to use this image
 
-## Start a java instance running your app
+## Start a Java instance in your app
 
-For this image, the most straight-forward use is to use a java container as both the build environment as well as the runtime environment. In your Dockerfile, you can do something along the lines of the following will compile and run your project.
+The most straightforward way to use this image is to use a Java container as
+both the build and runtime environment. In your `Dockerfile`, writing something
+along the lines of the following will compile and run your project:
 
     FROM java:7
     COPY . /usr/src/myapp
@@ -18,17 +23,20 @@ For this image, the most straight-forward use is to use a java container as both
     RUN javac Main.java
     CMD ["java", "Main"]
 
-Then run the commands to build and run the docker image.
+You can then run and build the Docker image:
 
     docker build -t my-java-app .
     docker run -it --rm --name my-running-app my-java-app
 
-## Compile your app inside the docker container.
+## Compile your app inside the Docker container
 
-It is not always appropriate to run your app inside a container. In instances where you only want to compile inside the docker instance, you can do something along the lines of the following.
+There may be occasions where it is not appropriate to run your app inside a
+container. To compile, but not run your app inside the Docker instance, you can
+write something like:
 
     docker run --rm -v "$(pwd)":/usr/src/myapp -w /usr/src/myapp java:7 javac Main.java
 
-This will add your current directory as a volume to the container, set the working directory to the volume, and run the command `javac Main.java` which will tell java to compile the code in Main.java and output the java class file to Main.class. Alternatively, if you have a make file, you can instead run the make command inside your container.
-
-    docker run --rm -v "$(pwd)":/usr/src/myapp -w /usr/src/myapp java:7 make
+This will add your current directory as a volume to the container, set the
+working directory to the volume, and run the command `javac Main.java` which
+will tell Java to compile the code in `Main.java` and output the Java class file
+to `Main.class`.