Allow users to pipe in the model via stdin
Allow users to pipe in the model via stdin

Hi,

I've been running or-tools with FlatZinc files that are assembled by a script. In my situation, it's much more convenient to pass the code in via stdin instead of saving it to a file first. Here are the modifications I've been using on my end to make that possible. They may well not be up to snuff with your coding standards (sorry; I'm not a C++ guy), but I wanted to put them out there in case you guys are willing to add that feature in :)
legrosbuffle/or-tools,2947721120/curly-hockeypuck,2947721120/curly-hockeypuck,lfiaschi/or-tools,google/or-tools,2947721120/or-tools,KapecK/or-tools,ThatRfernand/or-tools,linsicai/or-tools,2947721120/or-tools,linsicai/or-tools,linsicai/or-tools,WendellDuncan/or-tools,pombredanne/or-tools,google/or-tools,WendellDuncan/or-tools,pombredanne/or-tools,lfiaschi/or-tools,lfiaschi/or-tools,KapecK/or-tools,or-tools/or-tools,ThatRfernand/or-tools,2947721120/or-tools,linsicai/or-tools,or-tools/or-tools,google/or-tools,ThatRfernand/or-tools,2947721120/or-tools,2947721120/curly-hockeypuck,ThatRfernand/or-tools,linsicai/or-tools,lfiaschi/or-tools,KapecK/or-tools,WendellDuncan/or-tools,2947721120/or-tools,google/or-tools,ThatRfernand/or-tools,or-tools/or-tools,WendellDuncan/or-tools,pombredanne/or-tools,KapecK/or-tools,lfiaschi/or-tools,or-tools/or-tools,KapecK/or-tools,2947721120/curly-hockeypuck,linsicai/or-tools,legrosbuffle/or-tools,legrosbuffle/or-tools,2947721120/or-tools,legrosbuffle/or-tools,google/or-tools,2947721120/curly-hockeypuck,WendellDuncan/or-tools,pombredanne/or-tools,pombredanne/or-tools,KapecK/or-tools,or-tools/or-tools,google/or-tools,pombredanne/or-tools,lfiaschi/or-tools,WendellDuncan/or-tools,legrosbuffle/or-tools,or-tools/or-tools,2947721120/curly-hockeypuck