add ChangeLog file, and rename some documentation files

ChangeLog

@@ -0,0 +1,12 @@
+This file details the changelog of Capstone.
+
+
+[Version 2.0]: upcoming
+
+- See changelog at https://github.com/aquynh/capstone/wiki/ChangeLog
+
+
+[Version 1.0]: December 18th, 2013
+
+- Initial public release.
+

HACK.TXT

@@ -1,7 +1,7 @@
 Capstone source is organized as followings.
 
 
-.                   <- core engine + README + COMPILE etc
+.                   <- core engine + README + COMPILE.TXT etc
 ├── arch            <- code handling disasm engine for each arch
 │   ├── AArch64     <- ARM64 (aka ARMv8) engine
 │   ├── ARM         <- ARM engine
@@ -17,7 +17,7 @@ Capstone source is organized as followings.
 ├── tests           <- Test code (in C language)
 
 
-Follow COMPILE to see how to compile and run code.
+Follow instructions in COMPILE.TXT to see how to compile and run code.
 
 Note: if you find some strange bugs, it is recommended to firstly clean
 the code and try to recompile/reinstall again. This can be done with:

README

@@ -27,7 +27,7 @@ Further information is available at http://www.capstone-engine.org
 
 [Compile]
 
-See COMPILE file for how to compile and install Capstone
+See COMPILE.TXT file for how to compile and install Capstone
 
 
 [Status]
@@ -45,7 +45,7 @@ refer to the corresponding git repositories.
 
 [Hack]
 
-See HACK file for the structuture of the source code.
+See HACK.TXT file for the structuture of the source code.
 
 
 [License]