#2 Replace in files

[Peter]

A command to replace strings in files was always
requested by VisualHAM users.

It should have an option to find files in/from:
- active project
- all open documents
- a directory (with recursion as an extra option)

and an option to specify a filemask, to search in *.cpp
files only for example.

Other than that, it should have the same options as the
already implemented Replace dialog.