Closes #13: Convert index.md to kramdown syntax

The only major difference I noticed that we use is the fenced code block
format for GFM is different (using the backtick instead of the tilde).
If I missed anything, feel free to reopen the bug and tell me what, or
just submit a patch yourself!

docs/ivanx/index.md

@@ -168,9 +168,10 @@ carefully! — before copying the files.)
 
 You can also install A2CLOUD from the Raspbian command line. Type:
 
-```
+~~~
 wget appleii.ivanx.com/a2cloud/setup; source setup
-```
+~~~
+{: .language-sh}
 
 If you want all the features, answer “Y” to the questions. Then be patient, as
 it takes a little while to install.
@@ -262,9 +263,10 @@ If you don’t have A2CLOUD installed yet — because, for example, you installe
 vanilla NOOBS or Raspbian, rather than Raspple II — log in to your Pi, and at
 the Linux prompt type:
 
-```
+~~~
 wget ivanx.com/a2cloud/setup; source setup
-```
+~~~
+{: .language-sh}
 
 A2CLOUD is confirmed to work on Debian 7 (“Wheezy”), all releases of Raspbian,
 and possibly earlier versions of both. It is believed to work on other Debian
@@ -445,9 +447,10 @@ ADTPro by typing `a2cloud-update`.)` `
 If you need access to both slot 6 and the virtual drives at the same time, you
 can, after booting, type:
 
-```
+~~~
 -VSDRIVE.LOW
-```
+~~~
+{: .language-sh}
 
 However, this version of the driver for the virtual disks is easily
 overwritten by other software, especially if you exit BASIC.SYSTEM.  However,
@@ -737,9 +740,10 @@ explain in a later post.
 
 You can always put the A2CLOUD disk image back in virtual drive 2 with:
 
-```
+~~~
 vsd2 $A2CLOUD
-```
+~~~
+{: .language-sh}
 
 (The `vsd1` and `vsd2` commands create a symbolic link, which is like a
 Windows shortcut or Mac alias, to whatever file you specify as imageFileName.
@@ -1472,9 +1476,11 @@ as the default 4 MB disk in S2,D1.
 A2CLOUD can be installed on Debian or Ubuntu Linux (and possibly derivatives).
 It has been tried on the 32-bit versions of Debian 7 and Ubuntu Server 13.10.
 To install, type: 
-```
+
+~~~
 wget ivanx.com/a2cloud/setup; source setup
-```
+~~~
+{: .language-sh}
 
 You can also install it into the [A2SERVER][91] virtual machine with the same
 command, or start fresh with the premade [A2SERVER+A2CLOUD][91] virtual