Adds headers with minor version numbers to changelog

docs/changelog.md

@@ -1,5 +1,7 @@
 # Changelog
 
+### 1.9.x
+
 * **1.9.4** (22.11.2018)
     * fixes next version behavior when used with force snapshot - thanks to [Theer108](https://github.com/Theer108) and [trohr](https://github.com/trohr) for contribution
 * **1.9.3** (26.08.2018)
@@ -11,6 +13,9 @@
     * fixes behavior when two tags on the same commit - thanks to [lwasylkowski](https://github.com/lwasylkowski) for contribution
 * **1.9.0** (23.02.2018)
     * removes GrGit dependency
+
+### 1.8.x
+
 * **1.8.3** (30.01.2018)
     * fixes issue with obtaining SSH credentials - thanks to [Cliffred van Velzen](https://github.com/cliffred) for contribution
     * issue with ordering of tags when using alpha versions - thanks to [Cliffred van Velzen](https://github.com/cliffred) for contribution
@@ -22,6 +27,9 @@
 * **1.8.0** (07.10.2017)
     * allows on extending axion-release tasks - thanks to [Maria Camenzuli](https://github.com/maria-camenzuli) for contribution
     * moves travis builds to JDK 8 only - from this time on JDK 7 compatibility is no longer tested
+
+### 1.7.x
+
 * **1.7.2** (29.08.2017)
     * better performance when scanning for tags - lazy scan instead of reading all commits at once
     * adds graceful failure on version parsing problems
@@ -30,14 +38,26 @@
     * fixes error when working on project without Git repository
 * **1.7.0** (16.07.2017)
     * compatibility with Gradle 4.0
+
+### 1.6.x
+
 * **1.6.0** (13.04.2017)
     * added option to find highest version from all tags, not only current branch - thanks to [ProTrent](https://github.com/ProTrent) for contribution
+
+### 1.5.x
+
 * **1.5.0** (06.02.2017)
     * added ordering of tags by version when multiple found on single commit
+
+### 1.4.x
+
 * **1.4.1** (11.10.2016)
     * fixing critical bug in printing Git changes, which could block `verifyRelease` task
 * **1.4.0** (17.08.2016)
     * compatibility with Gradle 3.0
+
+### 1.3.x
+
 * **1.3.5** (23.06.2016)
     * added `tagSelector` option to choose from multiple tags on single commit - thanks to [levsa](https://github.com/levsa) for contribution
     * added snapshot dependencies check - thanks to [vbuell](https://github.com/vbuell) for contribution
@@ -56,6 +76,9 @@
 * **1.3.0** (11.07.2015)
     * support for custom version incrementation rules - thanks to [vbuell](https://github.com/vbuell) for contribution
     * ability to push only tags to remote repo - thanks to [erichsend](https://github.com/erichsend) for contribution
+
+### 1.2.x
+
 * **1.2.4** (03.05.2015)
     * support for pre-release versions (i.e. 2.0.0-rc2) - thanks to [vbuell](https://github.com/vbuell) for contribution
 * **1.2.3** (29.03.2015)
@@ -69,14 +92,21 @@
 * **1.2.0** (09.02.2015)
     * hooks - add custom actions before/after release
     * new documentation in RTD
+
+### 1.1.x
+
 * **1.1.0** (02.02.2015)
     * next version markers - ability to declare working on next major version
+
+### 1.0.x
+
 * **1.0.1** (15.01.2015)
     * support for setting custom key file/password in runtime
     * printing uncommitted changes on check failure
 * **1.0.0** (12.12.2014)
     * support for different means of authorization
 
+### Pre 1.0.0
 
 * **0.9.9** (01.12.2014)
     * added option to choose Git repository root