Make the new objects copy over values. They are essentially wrapper
types for the different decoders/builders.
* include/freetype/internal/psaux.h: Update declarations.
(PS_Builder): Add `is_t1' flag.
(PS_Decoder_{Get,Free}_Glyph_Callback): Renamed to...
(CFF_Decoder_{Get,Free}_Glyph_Callback: ... this.
(PS_Decoder): Updated.
Add `t1_parse_callback' member.
(PSAux_ServiceRec): Add `ps_decoder_init' member.
* src/psaux/psdecode.h, src/psaux/psobjs.h: Update declarations.
* src/psaux/psdecode.c, src/psaux/psobjs.c: Implement copy with two
modes.
* src/psaux/psauxmod.c: Add builder and decoder functions to `PSAux'
service.
Introduce `PS_Decoder' and `PS_Builder' which include all fields
from either Type 1 or CFF decoders/builders.
* include/freetype/internal/psaux.h (PS_Builder, PS_Decoder): New
structs.
* src/psaux/psobjs.c, src/psaux/psobjs.h: Add `PS_Builder'
functions.
* src/psaux/psdecode.c, src/psaux/psdecode.h: New files to hold
`PS_Decoder' initialization functions.
* src/psaux/psaux.c, src/psaux/Jamfile (_sources),
src/psaux/rules.mk (PSAUX_DRV_SRC): Updated.
