Fix fetch_{all_by,default_for}_Member()

The code was happily trying member_ids of the two kinds, but now that we
have split the tables, two members (a SeqMember and a GeneMember) can
have the same dbID.
When given a dbID, it is assumed to be a seq_member_id
Avoids the subfamilies when creating the clusters
TrimAl does remove members, and we need to check them in
Remove the member aligned with only gaps and Xs
Treebest can store its tree as raxml
Emits events on #2 and #3 when the cluster size is too small or too
large
RAxML does not work if less than 4 genes. Use TreeBest instead
Some jobs may need 64Gb of RAM
More memory for some analysis
New "use_notung" parameter + "entry_point" analysis
"split_genes" is included in tree_entry_point