Small additions/changes to track styles.
Added option to ignore global featureFilter for individual tracks via config.ignoreFeatureFilter.  
TODO: might want to generalize this as a featureFilter hook that can specify per-track filter?
Set default ignoreFeatureFilter = true for SequenceTrack, so that sequence alteration annotations are not affected by plus/minus strand feature filters.
Using monospace font to ensure that plus and minus strand input fields in new sequence alteration dialog are aligned, and also changing input text appearance to uppercase
Reworked sequence alteration annotation dialog so user can input residues on either plus or minus strand, and is mirrored on opposite strand.  Also limiting input to [acgtnACGTN].  Hiding opposite strand if input text length exceeds input element size, as this triggers text scrolling that can't (as far as I can determine) be synced in the opposite strand input element.