Add OTC font support for `-dfont-ps-resdir` (issue 548080043 by address@hidden)

[lemzwerg]

LGTM, with some nits


https://codereview.appspot.com/548080043/diff/573790043/Documentation/usage/running.itely
File Documentation/usage/running.itely (right):

https://codereview.appspot.com/548080043/diff/573790043/Documentation/usage/running.itely#newcode663
Documentation/usage/running.itely:663: this method cannnot embed CID
fonts with Ghostscript 9.26 and later.
s/cannnot/cannot/

https://codereview.appspot.com/548080043/diff/573790043/lily/open-type-font-scheme.cc
File lily/open-type-font-scheme.cc (right):

https://codereview.appspot.com/548080043/diff/573790043/lily/open-type-font-scheme.cc#newcode421
lily/open-type-font-scheme.cc:421: "ttcTag", collection.c_str ()));
Why "ttcTag"?  I would rather call this "TTC tag".

https://codereview.appspot.com/548080043/diff/573790043/lily/open-type-font-scheme.cc#newcode428
lily/open-type-font-scheme.cc:428: warning (_f ("font file `%s' is not
collection font",
s/not collection font/not a font collection/

https://codereview.appspot.com/548080043/diff/573790043/lily/open-type-font-scheme.cc#newcode437
lily/open-type-font-scheme.cc:437: warning (_f ("cannot read %s of
`%s'",
font `%s': cannot read `Version' field

https://codereview.appspot.com/548080043/diff/573790043/lily/open-type-font-scheme.cc#newcode446
lily/open-type-font-scheme.cc:446: warning (_f ("font file `%s' TTC
header version is unknown",
→ ... `%s': invalid TTC header version

https://codereview.appspot.com/548080043/diff/573790043/lily/open-type-font-scheme.cc#newcode455
lily/open-type-font-scheme.cc:455: warning (_f ("cannot read %s of
`%s'",
font `%s': cannot read `numFonts' field

https://codereview.appspot.com/548080043/diff/573790043/lily/open-type-font-scheme.cc#newcode478
lily/open-type-font-scheme.cc:478: warning (_f ("cannot read %s of
`%s'",
font `%s': cannot read offset of subfont %d

https://codereview.appspot.com/548080043/diff/573790043/lily/open-type-font-scheme.cc#newcode495
lily/open-type-font-scheme.cc:495: warning (_f ("cannot read %s of
`%s'",
→ font `%s': cannot read `sfntVersion' field of subfont %d

https://codereview.appspot.com/548080043/diff/573790043/lily/open-type-font-scheme.cc#newcode504
lily/open-type-font-scheme.cc:504: warning (_f ("font file `%s' index %d
does not have valid sfntVersion",
font `%s': invalid `sfntVersion' field in subfont %d

https://codereview.appspot.com/548080043/diff/573790043/lily/open-type-font-scheme.cc#newcode513
lily/open-type-font-scheme.cc:513: warning (_f ("cannot open font
filename `%s'",
→ cannot open font `%s' for writing

https://codereview.appspot.com/548080043/diff/573790043/lily/open-type-font-scheme.cc#newcode523
lily/open-type-font-scheme.cc:523: warning (_f ("cannot write %s of
`%s'",
font `%s': cannot write `sfntVersion' field

etc., etc. for remaining messages

https://codereview.appspot.com/548080043/