Add support for generic containers and C-style arrays

Extend the API with a generic function to support all kinds of containers and C-style arrays.

Properly handle negative values

Applying left shift operator on a negative value is an UB. The algorithm (step 3) describes how to properly encode negative values.

Fix the compiler warning

v2.0.1

Increment the version number

Refactor the build system and remove 'gpaf2' namespace

v2.0.0

Update the CI badge and documentation.

Ensure the backward compatibility

Merge pull request #11 from wolfee001/master

Backward compatibility change

Compiler error fix

Make it compile with older compilers such as MSVC 14.x.

Template class fix

Move class template definition into the header file and remove source file. This will prevent linker error on client side. Polylineencoder is now a single header library.

Configurable precision

This version of Polyline Encoder allows to configure coordinates precision. It's defaulted to the precision of five decimal places.