Extracting strings from sources

Localized strings can be easily extracted from .4gl and .per source files.

Use the fglcomp and fglform compilers with the -m option to extract localized strings.
$ fglcomp -m mymodule.4gl

The compilers dumps all localized string to stdout. This output can be redirected to a file to generate the default source string file with all the localized strings used in the source file. Source string files can then be re-organized, to centralize common messages in a unique .str file, and can then be compiled by fglmkstr into .4st files to be used by the runtime system.