Build searching for mappings in wrong place

[titusn]

Currently any project folder ending in the string mappings is used for generating Mapper.xill. This is not only not backwards compatible, it is also not in line with the Xill Project Convention, which states that mapping robots MUST be stored in a subfolder of config/ and MUST be called mapping/. It is especially bad since connectors SHOULD contain demo folders that have subfolders called mapping/.

Make sure that Build.xill only searches:

• subfolders of config/
• ending in mapping/