[Lazarus] Exclude components from localization by path or text

[Denis Kozlov]

I've implemented this feature and attached a patch:
http://bugs.freepascal.org/view.php?id=29627

In summary:
1) Added methods to remove entries from TPOFile by identifier and by 
original text.
2) Implemented storage of excluded identifiers and originals via TProject.
3) Updated translation routines to pass over project's excluded 
identifiers and originals when updating PO files.
4) Editing of excluded identifiers and originals in i18n project options.
5) Added option to "Force update PO files on next compile" in i18n 
project options (auto reset, non-persistent). To force update PO files 
after changing excluded identifiers and originals.

I hope this could be merged into either 1.4 or 1.6 as it's an extremely 
useful feature for i18n.

Denis