schema: improved mixedArrayFromString

Change-Id: Iff9d68a498e13e5a90cd68c07ee9986c3407a8cc
Merge branch 'master' of https://camlistore.googlesource.com/camlistore
gitignore: Ignore auto-generated file bin/hello.

Change-Id: I38e1eb056dbdd29ddabce620c9621cd22696839d
Merge branch 'master' of https://camlistore.googlesource.com/camlistore