Use the start.lua file in data/core as a template

Instead of having a separate start.lua.in file in the scripts directory
and no start.lua file in data/core we use the file data/core/start.lua
as a template for Meson to generate the final start.lua file for release.

In this way people naturally trying to run lite-xl from the source folder
will have a start.lua file albeit without a resolved version number.

Otherwise, when using run-local script or the meson install command the
meson-generated start.lua file will be used as it should be.

meson.build

@@ -16,11 +16,6 @@ conf_data.set('PROJECT_BUILD_DIR', meson.current_build_dir())
 conf_data.set('PROJECT_SOURCE_DIR', meson.current_source_dir())
 conf_data.set('PROJECT_VERSION', meson.project_version())
 
-configure_file(
-    input : 'scripts/start.lua.in',
-    output : 'start.lua',
-    configuration : conf_data
-)
 if host_machine.system() == 'windows'
     configure_file(
         input : 'scripts/innosetup/innosetup.iss.in',
@@ -117,13 +112,19 @@ endif
 
 install_data('licenses/licenses.md', install_dir : lite_docdir)
 
-foreach data_module : ['core', 'fonts', 'plugins', 'colors']
+install_subdir('data' / 'core' , install_dir : lite_datadir, exclude_files : 'start.lua')
+foreach data_module : ['fonts', 'plugins', 'colors']
     install_subdir('data' / data_module , install_dir : lite_datadir)
 endforeach
 
-install_data(
-    meson.current_build_dir() / 'start.lua', install_dir : lite_datadir / 'core'
+configure_file(
+    input : 'data/core/start.lua',
+    output : 'start.lua',
+    configuration : conf_data,
+    install : true,
+    install_dir : lite_datadir / 'core',
 )
+
 #===============================================================================
 # Targets
 #===============================================================================

scripts/run-local

@@ -76,10 +76,13 @@ copy_lite_build () {
     cp "$builddir/src/lite-xl" "$bindir"
   fi
   mkdir -p "$datadir/core"
-  cp "$builddir/start.lua" "$datadir/core"
   for module_name in core plugins colors fonts; do
     cp -r "data/$module_name" "$datadir"
   done
+  # The start.lua file is generated by meson in $builddir but
+  # there is already a start.lua file in data/core so the command below
+  # should be executed after we copy the data/core directory.
+  cp "$builddir/start.lua" "$datadir/core"
 }
 
 run_lite () {