GitLab

Merged the other-tags branch into the trunk (this wasn't an rX:Y merge, since the branch wasn't branched directly from the head of the trunk)

Moved all the includes to a subfolder yaml-cpp so they don't interfere with other libraries' includes

Fixed leak when adding duplicate keys (and actually changed the behavior - now we take the first instance, not the last)

Refactored emitter operator << overloads to not template them, so it's easier to overload for pointer types

Fixed flow folding, and made the separation slightly cleaner (but the whole scanscalar thing could use a major refactoring)

(Actually) fixed the folding newline bug, but it's a bit messy, and we don't accurately make the distinction between block folding and flow folding

Refactored the operator >> and Node::Read default functions, as well as the conversion functions, to more easily read new types as keys (this uncovered an error, in example 2.11 of the spec)

Added templated casting to nodes, as well as operator == and != (for quick checks, especially to help in testing). Implemented size() on a map node to return the number of key/value pairs (as in std::map)