Fix R outside due to float32 rounding

[terliuk]

What is the problem / what does the code in this PR do

Fix for bug where instructions are flagged outside of the TPC due to the float32 rounding. Fixes #384

[coveralls]

Coverage decreased (-0.1%) to 82.584% when pulling 4f3ab4e on fix_rounding_tpc into 69e7095 on master.

[ramirezdiego]

Shouldn't you also modify these lines?

WFSim/wfsim/strax_interface.py

Lines 858 to 860 in 69e7095

	assert np.all(self.instructions_epix['x']**2 + self.instructions_epix['y']**2 <
	self.config['tpc_radius']**2), \
	"Interaction is outside the TPC (radius)"

[PavelKavrigin]

@terliuk - I do not see the assertion error anymore when I use this branch and "undo_1mm_context" branch of cutax, with the same example input file which I used for reporting the issue.