Adding documentation for previously added functions.

[SharonIV0x86]

The following functions are missing documentation.

int str_hashcode(const char* str) 

hash code function

int str_larg_word(char * p, char * r)

large word function

int str_small_word(char * p, char * r)

small word function

README.md is to be updated here
Use the existing documentation format, Refer to the image down below to get an idea of the markdown file.

[AbhinavBarthwal]

Allow me to add the required documentation .
I'll make sure to work with the best of my abilities.

[SharonIV0x86]

Allow me to add the required documentation . I'll make sure to work with the best of my abilities.

How is it going?