syntastic 3.2.0

Core changes

• Allow g:syntastic_filetype_map to apply to composite filetypes (@lcd047)
• Re-read g:syntastic_mode_map at each attempted check (@lcd047)
• New config variable g:syntastic_delayed_redraws (@lcd047)
• New config variable g:syntastic_id_checkers (@lcd047)
• Various bugs have been fixed.

Syntax checker changes

• Added swiffer checker for Dust.js (@smfoote)
• Rework of the gcc checkers (@lcd047)
• Rework of the perl checker (@lcd047)
• Added handlebars checker for Handlebars (@mutewinter)
• Added foodcritic checker for Chef (@dougireton)
• Added rubylint checker for Ruby (@yorickpeterse)
• Added shellcheck checker for sh (@lcd047)
• Added scss_lint checker for SCSS (@sds)
• Various bugs have been fixed.