Changed package description.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/eventstudies@234 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Removed extra comma.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/eventstudies@235 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Modified details for eventstudy function

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/eventstudies@236 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Minor edit

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/eventstudies@237 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Modified the value section, included more detail on the AMM class and functions.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/eventstudies@238 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Minor edit

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/eventstudies@239 edb9625f-4e0d-4859-8d74-9fd3b1da38cb