Allow Ranges on Rash to match _all_ Numerics

Previously, it checked only for Integers; unfortunately,
that left Floats out, so passing in a float would cause
it to look it up normally.  This also changes the range
checking to `cover?` instead of `include?`.  Also
adds a line to a test to check for float availability.
Merge pull request #184 from medcat/rash-numeric-access

Allow Ranges on Rash to match all Numerics
Minor CHANGELOG update.
spec + implementation

we can now become a fisher by extending a fish :)

include pretty inspect... because it's pretty

add doc

fish is now cash

add todo

update changelog and readme

cash -> yash

format will always be yml

folder_path is a required param

set default namespace through class variable

better method names for less confusion

add ability to load specific yml file

load file from yash and improve extend

better spec and rename alias method

cleaner API, better specs

re write the doc and small bring namespace to the file_to_mash

update readme