New docs
Start to develop the class irc (Interest Rate Curve)

I want to go on with R-fixedincome.
I will use short class names to get closer of the R style.
Integrate with bizdays and other features.
Regenerating docs and implementing new tests for irc

Implemented new test for `irc`.
Examples to follow
I need the frequency.
Huge change

- Old classes have been moved to legacy.
- new classes:
	- spotrate
	- daycount
	- term
	- compounding
Removed references to old methods
Updating docs

Writing and updating docs.
Organizing docs
New docs for classes
Organizing docs
Updated docs
Creating examples
Docs and examples updated
Rbuildignore updated
spotrate and compounding coercion functions

- as.spotrate.character returns a list because it can return spotrates with different settings
- as.compounding.character
- lft.R updated
- docs updated
Added NEWS
Docs updated

- new function `as.list.spotrate`
Docs updated
Merge pull request #2 from wilsonfreitas/1

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