v2.16.0: all: add Bazel BUILD files

• Add BUILD.bazel files (#88)

v2.15.0

• capnpc-go now fails when a file does not include an import annotation. (#41)
• Remove rbtree dependency (#80)
• Add option to reduce allocations in capnp.Decoder (#79)
• Add String() methods for lists (#85)
• Add String() methods to schema.capnp.go (#83)

v2.14.1: capnpc-go: use new generated code convention

• Use new Go generated code convention in capnpc-go output (#78)