LigatureCaret in FEA wrong syntax - now updated to LigatureCaretByPos

First Described here: [Fontforge-devel] LigatureCaret in FEA wrong syntax
http://sourceforge.net/mailarchive/message.php?msg_id=30850289

Should resolve issue: https://github.com/fontforge/fontforge/issues/570
Fix reading anchors from feature files

markClass accepts a single glyph or a glyph class.
Fix anchor names sometimes showing garbage

Anchor names could sometimes show garbage in CharView with Pango printing
warning about invalid text. Increased string length and Appended a '\0'.
Merge pull request #573 from JoesCat/master

  [Fontforge-devel] LigatureCaret in FEA wrong syntax - issue#570