Charmap module initialized
Code improvements
Improve the function by avoiding passing size
Use strings directly rather than juggling between rune and string
Updated test cases.
Introduce english alphabets in series
Fix the buggy initialization code which was overwriting soundex_in and soundex_in sequences
Formatting fix
SoundexCode implemented to return soundex code for a give char
Added missing en_US alphabets to langMap
Error handling for charmap module UnknownCharError
Improved test cases
Fix the code to work around Go's unicode knowledge

Go doesn't understand unicode code points correctly so for Indian
languages using char as string might cause trouble so define
runeSequence.

ISO15919 and IPA are not exactly single chars instead multibyte chars
so use them as strings.

Additionally made the sequenceIndex function index generic by making
it accept interface{} types. Also modified error handling to reflect
this change.
Replace all string literals as rune literals simple replace of ` with '
Use runeSequence in places where it is required.
Generic interface{} type arguments and runeSequence usage implemented
Don't mix and match rune and string in generic interface{} type
slice. Go runtime will go mad if this is done
Fixed test cases
Documentation and code formatting