Rename freedesktop and metainfo files to reverse DNS schema

Based on the suggestion made by Mart Raudsepp.

"Regular installs should have reverse DNS notation desktop and
metainfo files as well. This becomes important if we ever make use
of things like dbus service activation further down the line. And
renaming it then will break peoples app shortcuts and other things."

Signed-off-by: Leon Marz <main@lmarz.org>
Signed-off-by: Panagiotis Vasilopoulos <hello@alwayslivid.com>
Helped-by: Mart Raudsepp <leio@gentoo.org>
Reference-to: https://github.com/tenacityteam/tenacity/pull/642

help/CMakeLists.txt

@@ -51,8 +51,8 @@ if( NOT CMAKE_SYSTEM_NAME MATCHES "Darwin" )
    if( NOT WIN32)
       install( DIRECTORY "${dst}" OPTIONAL
                DESTINATION "${_DATADIR}/tenacity/help" )
-      
-      install( FILES "${_SRCDIR}/tenacity.metainfo.xml"
+
+      install( FILES "${_SRCDIR}/org.tenacityaudio.Tenacity.metainfo.xml"
                DESTINATION "${_DATADIR}/metainfo" )
    endif()
 endif()
@@ -64,7 +64,7 @@ cmake_dependent_option(BUILD_MANPAGE "Build manpage" ON "NOT SCDOC_CMD STREQUAL
 
 if( BUILD_MANPAGE )
    add_custom_command( COMMENT "Generating manpage"
-      COMMAND ${SCDOC_CMD} < "${_SRCDIR}/tenacity.1.scd" > "${CMAKE_BINARY_DIR}/help/tenacity.1" 
+      COMMAND ${SCDOC_CMD} < "${_SRCDIR}/tenacity.1.scd" > "${CMAKE_BINARY_DIR}/help/tenacity.1"
       DEPENDS "${_SRCDIR}/tenacity.1.scd"
       OUTPUT "${CMAKE_BINARY_DIR}/help/tenacity.1" )