Fix bug saving large numbers of strings

Merge pull request #32 from simonster/sjk/fix31

Don't put >65535 strings in a heap (fixes #31)

Fix some bugs

Merge pull request #29 from simonster/fbot/deps

Fix deprecations

Fix potential segfault when writing Dicts

v0.0.2

Add AppVeyor badge

v0.0.1: Merge pull request #17 from simonster/sjk/workaround-22592

Workaround JuliaLang/julia#22592 by rearranging code