Add a licence, reflecting existing assumptions

Patch from Bernhard R Link to allow setting new window command in compile option

Patch from Bernhard R Link for const correctness of strings

Patch from Bernhard R Link to make wm2 64-bit clean

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fix a compile warning.

Fixes merged from Debian wm2_4-7 package.

build fixes

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Importing wm2-4

Importing wm2-3

Importing wm2-2

Importing wm2-1