Modify update() method to create a row in analysis_description if the analysis exists but doesn't have a description.
If there is already a description, it gets updated.

Changed update() and remove() methods to include analysis_description table as well.

Updated to deal with new way of handling cisred factors. Parsing now simpler, has support for features which don't have an associated factor.

Add ;mysql_local_infile=1 to DBI initialisation call to work around MySQL change that causes errors such as

	DBD::mysql::db do failed: The used command is not allowed with this MySQL version
	at /nfs/acari/gp1/work/ensembl-test/modules/Bio/EnsEMBL/Test/MultiTestDB.pm line 313.

when using LOAD DATA INFILE.