Translation wrapper

@Vaydheesh trying to make sure we keep track of what you're working on a bit in the issues as well. Just assign yourself to the relevant issue as you're working on it (or create a new one). https://github.com/apertium/apertium-python/issues/48#issuecomment-507043217

Lttoolbox/Hfst:

- [x] `lrx-proc`
- [ ] `lsx-proc` https://github.com/apertium/apertium-separable/blob/master/src/Makefile.am#L8
- [x] `apertium-pretransfer`
- [x] `apertium-transfer`
- [X] `apertium-tagger`
- [x] `apertium-interchunk`
- [x] `apertium-postchunk`

Hfst:

- [x] `cg-proc` https://github.com/TinoDidriksen/cg3/blob/master/src/cg_proc.cpp
- [ ] `cg-conv` https://github.com/TinoDidriksen/cg3/blob/master/src/cg_conv.cpp
- [ ] `hfst-proc` https://github.com/hfst/hfst/tree/master/tools/src/hfst-proc
- [ ] `vislcg3`