Initial commit
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Add a sqrt procedure implementation
Use lexical scoping in my-sqrt
Add cube root implementation
Test normal order or applicative order
Add circular function definition examples
Add several procedure implementations
Add example for enabling srfi module
Add iterative implementation
Add utils module
Add some comments

Try deep block structure by moving change-coins inside iter-cc
and rename it to cc.
Add sine analysis
Add fast-expt procedure
Subsititue if with an extra cond predicate
Add multiply procedure
Add several fibonacci procedures
Analyze applicative order and normal order for gcd
Add a space
Add prime procedures