Accept Emitter::operator<<(std::string_view).
ABI remains C++11 compatible by exposing new method
Emitter::Write(const char*, size_t).
All affected calls optimized to pass std::string values as pointer + size
tuple into appropriate routines.
Add dragonbox to compute the required precision to print floating point
numbers. This avoids uglification of floating point numbers that
happen by default via std::stringstream.
Numbers like 34.34 used to be converted to '34.340000000000003' as strings.
With this version they will be converted to the string '34.34'.
This fixes issue https://github.com/jbeder/yaml-cpp/issues/1289
For completeness I've implemented escaping for characters outside the
basic multilingual plane, but it doesn't get used (as there's no
EscapeAsAsciiJson emitter option implemented).
Inside of a sequence or map, `YAML::Newline` wouldn't reset the collection state, which would cause behavior like this:
```
nodeA:
k: [{i: 0},
{i:1},
]NodeB:
k: [{i: 0},
{i:1},
]
```
The issue is that numbers like
2.01 or 3.01 can not be precisely represented with binary floating point
numbers.
This replaces all occurrences of 'std::numeric_limits<T>::digits10 + 1' with
'std::numeric_limits<T>::max_digits10'.
Background:
Using 'std::numeric_limits<T>::digits10 + 1' is not precise enough.
Converting a 'float' into a 'string' and back to a 'float' will not always
produce the original 'float' value. To guarantee that the 'string'
representation has sufficient precision the value
'std::numeric_limits<T>::max_digits10' has to be used.
