This directory is  the default location for installing NCBI BLAST databases.
During a BIRCH install, the BLASTDB environment variable will be set to
$BIRCH/GenBank.

To install databases in a different location, there are two
ways to do it.

1. blastdbkit.py --configure --blastdb <directory name>

OR

2. Delete the GenBank directory and create a symbolic link
called GenBank that points to an existing directory.
For example, if you want your BLASTDB directory to be 
/workspace/GenBank, 

cd $BIRCH
rm -rf $GenBank
ln -s /workspace/GenBank