Update version and changelog for 1.6.0

Author: ahayworth

.version

@@ -1 +1 @@
-1.5.4
+1.6.0

doc/CHANGELOG.md

@@ -8,6 +8,16 @@
 </tr>
 </thead><tbody>
 
+<tr valign=top>
+<td>1.6.0</td>
+<td>
+<li><a href="https://github.com/github/octocatalog-diff/pull/216">#216</a>: (Enhancement) Hide sensitive parameters</li>
+<li><a href="https://github.com/github/octocatalog-diff/pull/204">#204</a>: (Enhancement) Add glob support for modulepath</li>
+<li><a href="https://github.com/github/octocatalog-diff/pull/206">#206</a>: (Bug Fix) Fix multi-node list with parallel mode</li>
+<li><a href="https://github.com/github/octocatalog-diff/pull/215">#215</a>: (Bug Fix) Add Support for Hashdiff 1.0.0</li>
+</td>
+</tr>
+
 <tr valign=top>
 <td>1.5.4</td>
 <td>2018-12-11</td>