Merge remote-tracking branch 'kiliman/master' (#185)

* OperatorMonoSSm (Light, Book, Medium, Bold)
New Ligatures:
    - colon_colon
    - exclam_exclam
    - semicolon_semicolon
    - less_less
    - greater_greater
    - hyphen_equal (minus_equal)
    - asterisk_equal
    - slash_equal
    - less_slash_greater
    - less_less_equal
    - quotedbl_quotedbl_quotedbl
    - quotesingle_quotesingle_quotesingle
New Powerline Glyhps:
    - E0A1 (Powerline LN)
    - E0A2 (Powerline lock)
    - E0B1 (Powerline left soft divider)
    - E0B3 (Powerline right soft divider)

Features:
    - ss10 can be used to substitute 'x' for '×'. Eg 0×FF or 800×600
    - 'Equality Spaces' and 'Less-than/Greater-than Horizontal Bar' alternatives are included
    by default, and can be activated via ss11 and ss12 respectively.
    - Corrected and simplified features code to include the missing 'kern' feature for
    fraction numerator and denominator positioning.
    - 'calt.js' will also generate the 'liga' feature.

Edited and repositioned some existing glyphs to be more consistent across font weights.
Created missing glyphs for other weights. Eg 'w_w_w.liga' and 'plus_equal.liga'

* 'calt.js' no longer generates the 'liga' feature.

* Adjusted hinting, no contours changed.

ligature/OperatorMonoSSmLig-BoldItalic/glyphs/asterisk_equal.liga.xml

@@ -0,0 +1,21 @@
+<Glyph name="asterisk_equal.liga" lsb="-508" width="625">
+    <CharString>
+        76 -21 97 132 -28 139 0 131 67 -20 hstemhm
+        hintmask 11011000
+        530 526 rmoveto
+        -472 hlineto
+        -27 -131 rlineto
+        473 hlineto
+        -21 -111 rmoveto
+        -473 hlineto
+        -27 -132 rlineto
+        473 hlineto
+        -657 -97 rmoveto
+        94 37 rlineto
+        hintmask 10101000
+        -29 164 167 39 -6 100 -165 22 15 168 -99 28 -75 -153 -151 70 -58 -85 123 -120 -111 -122 63 -80 149 77 rlineto
+        endchar
+    </CharString>
+    <Subrs/>
+    <GlobalSubrs/>
+</Glyph>