Jenkins symlink

[lilawren]

Need a better solution than the symlink fix for the unit testing server.

[nickrsan]

OK, so here's my plan for fixing this:

1. Change the spreadsheets that provide the input regions to remove {{BASE_DIR}}
2. Remove the code that processes {{BASE_DIR}} to the actual BASE_DIR variable
3. Add a function with the @Property decorator tho handle setting and getting the value for each of the major attributes
4. Add private variables for each attribute that store the real values, while continuing to access the value through the current names. The real names will be composed by the function by combining the base_dir and the remaining portion of the path from the private variable. The setter will check if the set path is absolute. If it is, and the first part matches BASE_DIR, it will strip off BASE_DIR from the front and store the rest in the private attribute (thus allowing other data outside of BASE_DIR to be used, although that should be frowned on during development)

[nickrsan]

@lilawren you might be interested in the implementation of this fix - check out the models code for regions - the first few methods handle this problem.