ldc2.conf: %%ldcconfigpath%% support added

[denizzzka]

Fix #4714

[thewilsonator]

Thanks, could you add this to the changelog as well as some documentation.

[denizzzka]

Changelog record added

There is no documentation for %%ldcbinarypath%% placeholder, so I don't know where and what to write

[thewilsonator]

There is no documentation for %%ldcbinarypath%% placeholder, so I don't know where and what to write

Hmm, will wait for others to hopefully give some guidance.

[kinke]

Thanks!