Naming consistency

[kchall]

Rename functions to make them consistent across levels (e.g. pct_funcload_gui.py and pct_funcload_cl.py; funcload_io.py, neighdens_io.py, etc.).

See also #492 .

Use the following:

freqalt
funcload
neighdens
phonosearch
phonoprob
preddist
kldiv
stringsim (instead of symbolsim)
acousticsim
mutualinfo

@mdfry -- do this for the file structure, function calls, tests, and GUI

[kchall]

My notes on specifics:
functions: lower_case
classes: CamelCase
use _ in front of function name to indicate an embedded function (only in extremely clear cases of embedded function; err on the side of non-underscored)

[kchall]

Do this before writing new tests.
@bhallen can do the all _ additions for the analysis functions

@bhallen , @mdfry double check that this has been done before we move on to new tests

[devyn]

• Analysis files
• GUI files
• Test files

Make consistent.

[kchall]

also keep "select" and "selection" consistent