Add inplace TileFetcher options back to public builder API

[njmei]

This commit addresses an import error encountered
when trying to import inplace TileFetcher functionality.

Though if you want to keep the inplace stuff a secret
option for now, that's understandable too...

Example failing import:

from starfish.experiment.builder.inplace import (
    InplaceFetchedTile,
    enable_inplace_mode,
    inplace_tile_opener)

[codecov-io]

Codecov Report

Merging #1375 into master will decrease coverage by 1.29%.
The diff coverage is 0%.

@@           Coverage Diff            @@
##           master   #1375     +/-   ##
========================================
- Coverage   90.49%   89.2%   -1.3%     
========================================
  Files         217     148     -69     
  Lines        8304    5374   -2930     
========================================
- Hits         7515    4794   -2721     
+ Misses        789     580    -209

Impacted Files	Coverage Δ
starfish/experiment/builder.py	0% <0%> (ø)	⬆️
starfish/core/experiment/test/test_experiment.py
starfish/core/recipe/test/test_runnable.py
starfish/core/spacetx_format/test/test_validate.py
starfish/core/imagestack/test/test_export.py
...table/test/test_stack_intensity_table_reshaping.py
...rfish/core/intensity_table/test/test_to_mermaid.py
starfish/core/test/factories.py
...tarfish/core/image/_filter/test/test_call_bases.py
starfish/core/test/test_synthetic_spot_creation.py
... and 60 more

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[njmei]

@ttung: Rebased/squashed so that this is only 1 commit. Please merge if everything looks good and tests pass.