Check a cell with certain name exists

[GoogleCodeExporter]

We need a tell function reporting whether a cell with certain name exists in 
the db.
Possibly - the existing functions for open/edit cells can be revisited and 
updated with options like:
- create if not existing
or simply make the functions return a status - like:
- can't create - it's existing
- can't open - it's not existing

Original issue reported on code.google.com by krustev....@gmail.com on 27 Mar 2014 at 11:12

• Blocking: #177

[GoogleCodeExporter]

Updates in r2437.

New function added:
bool checkcell(string cell_name, bool editable);

if (editable) 
   return true if cell_name exists and is editable (i.e. not a library cell)
else
   return true cell_name exists 

Also:
opencell now returns true on success 
newcell now return false if the cell with this name already exists

Original comment by krustev....@gmail.com on 28 Mar 2014 at 11:38

• Changed state: Fixed

[GoogleCodeExporter]

Closing this batch of tell related new features

Original comment by krustev....@gmail.com on 12 Apr 2014 at 12:56

• Changed state: Verified

[GoogleCodeExporter]

Original comment by krustev....@gmail.com on 12 Apr 2014 at 1:03

• Now blocking: #177