GitLab

* Add compilation flags: -Wshadow -Weffc++ -pedantic -pedantic-errors
* Delete implicit copy & move constructors & assignment operators
  in classes with pointer data members.
* An exception to the above: Add default copy & move constructors &
  assignment operators for the Binary class.
* Convert boolean RegEx operators to binary operators.
* Initialize all members in all classes in ctors.
* Let default ctor delegate to the converting ctor in
  Binary and RegEx
* Don't change any tests except regex_test (as a result of the change
  to binary operators).

Note: https://bugzilla.redhat.com/show_bug.cgi?id=1544675 makes
-Weffc++ report a false positive in "include/yaml-cpp/node/impl.h".

* Removed an expression which is always true
* The second expression (ch is space) is removed because the first one contains space 0x20
* nextEmptyLine is always false so it is removed from the expression

Switched the stream << for c-strings to take a templated array param (since we never stream user-built c-strings, only string literals). For this, refactored the escape character display

Renamed the base64 methods, and switched the EncodeBase64 one to return a string (to make it easy to use elsewhere)

Refactored the base64 binary to its own space with a unified class that (will) be used for parsing (in addition to emitting)

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

Converted indexing to std::size_t, and fixed the Node templated overloads to properly index any index type (determining what is an index type is a bit of a hack - it should be is_convertible<T, std::size_t> (I think), but I just explicitly wrote down a list)