[CMake] Allow building only shared or static libraries

Both shared and static libraries are built by default. It would be nice to only build one or the other. 

For example, move `add_library(ta-lib-static STATIC ${LIB_SOURCES})` and similar, to be built conditionally via an `option`. 

```cmake
option(BUILD_STATIC_LIBS "Build Static Libraries" OFF)

if (BUILD_STATIC_LIBS)
    add_library(ta-lib-static STATIC ${LIB_SOURCES})
...
```