Merge pull request #4 from moriarty82/master

Another test pull request
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File I/O operations ready

App now capable of maintaining session records in application's private
data.
Strings list updated
Basic UI features

Simple UI features like sliding panels added. Now possible to create,
end and delete sessions.
Add participants

Now possible to add participants in session, properly displayed in
ListView. Also fixed ConcurrentModificationException.
Add participants

Now possible to add participants in session, properly displayed in
ListView. Also fixed ConcurrentModificationException.
Basic Log UI features have landed

A non-functional UI for displaying session logs has been added, with
features like adding new participants, editing session name and ending
session.
AccountRecord modified

Unnecessary methods removed, variables initialized, balance calculation
added to reduce code