fontsrv: handle non-BMP runes on X11 Have to adjust algorithms to deal with much larger number of subfont files as well.

libdraw: redo default font construction to be hidpi-safe If $font is not set, the default font is constructed from font data linked into every libdraw binary. That process was different from the usual openfont code, and so it was not hidpi-aware, resulting in very tiny fonts out of the box on hidpi systems, until users set $font. Fix this by using openfont to construct the default font, by recognizing the name *default* when looking for font and subfont file contents. Then all the hidpi scaling applies automatically. As a side effect, the concept of a 'default subfont' is gone, as are display->defaultsubfont, getdefont, and memgetdefont.

fontsrv: use 64 chars per subfont instead of 256 Makes loading faster, and makes larger sizes not too wide. Change-Id: I076c83fdb9577c1e596de45558f38ea93e3a2a31 Reviewed-on: https://plan9port-review.googlesource.com/1360 Reviewed-by: Russ Cox <rsc@swtch.com>

fontsrv: use CoreText API on OS X This gets us font fallback for free and avoids use of a deprecated API that might go away some day. Change-Id: I4b9b1a1ce3e6d98bfb407e3baea13f4adfe2c26a Reviewed-on: https://plan9port-review.googlesource.com/1160 Reviewed-by: Russ Cox <rsc@swtch.com>

fontsrv: scaled pjw R=rsc https://codereview.appspot.com/6854130

fontsrv: x11 support R=rsc, 0intro CC=plan9port.codebot http://codereview.appspot.com/6739047

merge