Doc: convert readme from txt to markdown

docs/CMakeLists.txt

@@ -16,7 +16,7 @@ install(FILES
 	${CMAKE_CURRENT_SOURCE_DIR}/grftut.txt
 	${CMAKE_CURRENT_SOURCE_DIR}/nforenum.txt
 	${CMAKE_CURRENT_SOURCE_DIR}/readme.rpn.txt
-	${CMAKE_CURRENT_SOURCE_DIR}/readme.txt
+	${CMAKE_CURRENT_SOURCE_DIR}/readme.md
 	${CMAKE_CURRENT_SOURCE_DIR}/sanity.txt
 	${CMAKE_CURRENT_SOURCE_DIR}/todo.txt
 	DESTINATION ${CMAKE_INSTALL_DOCDIR}

docs/readme.txt → docs/readme.md

@@ -1,21 +1,21 @@
+# grfcodec
 GRF development tools README
+
 Last updated:    2016-06-27
+
 Release version: 6.0.6
-------------------------------------------------------------------------
 
+## Table of Contents
 
-Table of Contents:
-------------------
-1) About
-2) Contact
-3) Installation
-4) Running
-5) Known issues
-6) Compiling
+- 1.0) About
+- 2.0) Contact
+- 3.0) Installation
+- 4.0) Running
+- 5.0) Known issues
+- 6.0) Compiling
 
+## 1.0) About
 
-1) About:
--- ------
 The GRF development tools are a set of tools for developing (New)GRFs.
 It includes a number of smaller programs, each with a specific task.
 
@@ -39,16 +39,14 @@ NFORenum is licensed under the GNU General Public License version 2, or at
 your option, any later version. For more information, see 'COPYING'
 (GPL version 2), or later versions at <http://www.gnu.org/licenses/>.
 
+## 2.0) Contact
 
-2) Contact:
--- --------
 Contact can be made via the issue tracker / source repository at
 https://github.com/OpenTTD/grfcodec or via IRC on the
 #openttd channel on OFTC.
 
+## 3.0) Installation
 
-3) Installation:
--- -------------
 Installing the GRF development tools is fairly straightforward. Just copy
 the executable into any directory. It is advised to put the executable in
 one of the directories in your path so it can be easily found. For example
@@ -60,14 +58,12 @@ It is not necessary to remove the .nforenum directory before upgrading.
 
 To uninstall, delete the executables and any .nforenum directories.
 
+## 4.0) Usage
 
-4) Usage:
--- ------
 Information about the usage of the different tools can be found in their
 respective man pages as well as grfcodec.txt, grftut.txt and nforenum.txt.
 
+## 6.0) Compiling
 
-6) Compiling:
--- ----------
 GCC/ICC:
   Just use "make", or on non-GNU systems "gmake".