refactor(build): Remove version number namespace

I don't know the original intention behind this but it clutters up debug
traces and basically makes ccache useless.

The only benefit it has, giving version info in stacktraces, is kind of
void since we already ask for version information on github issues.

CMakeLists.txt

@@ -40,8 +40,6 @@ else()
   set(APP_VERSION "${version_txt}")
 endif()
 
-STRING(REGEX REPLACE "[^a-zA-Z0-9_]" "_" APP_VERSION_NAMESPACE "v${APP_VERSION}")
-
 set(CMAKE_MODULE_PATH
   ${CMAKE_MODULE_PATH}
   ${PROJECT_SOURCE_DIR}/cmake

include/common.hpp

@@ -8,10 +8,8 @@
 #include "settings.hpp"
 
 #define POLYBAR_NS    \
-  namespace polybar { \
+  namespace polybar {
-    inline namespace APP_VERSION_NAMESPACE {
 #define POLYBAR_NS_END \
-  }                    \
   }
 
 #ifndef PIPE_READ

include/settings.hpp.cmake

@@ -6,7 +6,6 @@
 
 #define APP_NAME "@PROJECT_NAME@"
 #cmakedefine APP_VERSION "@APP_VERSION@"
-#cmakedefine APP_VERSION_NAMESPACE @APP_VERSION_NAMESPACE@
 
 #cmakedefine01 ENABLE_ALSA
 #cmakedefine01 ENABLE_MPD