Add terminus PSF fonts

Terminus/PSF/README.markdown

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+Terminus PSF (PC Screen Font) type 2 files with embedded unicode table.
+
+Used primary in linux EGA/VGA console. As it is required for the font to contain 
+exactly 256 or 512 characters and terminus already used all of them this font 
+files have the following glyphs substituted with the powerline glyphs:
+
+    Codepoint  Character  Name
+     U+2320        ⌠      TOP HALF INTEGRAL
+     U+2321        ⌡      BOTTOM HALF INTEGRAL
+     U+20A7        ₧      PESETA SIGN (Spain currency sign)
+     U+00BE        ¾      VULGAR FRACTION THREE QUARTERS
+     U+00B3        ³      SUPERSCRIPT THREE
+     U+00AC        ¬      NOT SIGN (angled dash)
+     U+221A        √      SQUARE ROOT
+
+Note: “substituted” means that these codepoints and these glyphs were removed 
+and new glyphs and new codepoints were added. Powerline symbols are accessible 
+using the usual codepoints, not above ones.