TODO
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18/05/2016

Main features to achieve before v1.0
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1. Complete calc chain and fix known issues regarding undoing
changes that impact in cells on which other cells depends on.

2. lock / freeze a section of the screen (rows or columns).

3. Export spreadsheet to Latex format.



Long term features
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1. isolate UI code (CURSES) from the rest of the code for future
implementations in other gui's.

2. scim_scripting. Use LUA to allow scripting and plugin support.

3. status bar format customized by user.
can show count of cells and sum of values, when a range is selected..
*this should be done with a script.