Added contig_insert_bases() and sequence_insert_bases() functions to
insert multiple bases of the same base/conf. Practically speaking that
just means runs of pads, however it sometimes has a major speed
improvement to the join editor and possibly shuffle pads.


git-svn-id: https://staden.svn.sourceforge.net/svnroot/staden/staden/trunk@3240 ba6f2710-ca9f-427c-89d3-5bf716dbc8e1