Add objc_args in meson when compiling to pass C defines also to
bundle_open.m.
Default "bundle" option to false to have by default a unix-like
build and install.
In the run-local script always expect that "bundle" option is to
false to have a unix-like install.
In the build-package script pass the -Dbundle=true option when
building on macos.
When setting the resouce path revert to original method using
[[NSBundle mainBundle] resourcePath]
to have the real resource path when the bundle option will be
activated. With the recent commit the function
set_macos_bundle_resources will be called only if the "bundle"
option is activate and is not used in unix-like mode.
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.