An example of automatic series expansion while eval() of tanh()
Automatic series expansion while applying a function
Revert "An example of automatic series expansion while eval() of tanh()"

This reverts commit 3e2fca83cb3f386af28de0706b0c379e55b9b876.
Catch NotImplementedError for f(series), where f is UndefinedFunction
Cleanup
automatic evaluation for multiple arguments
Fixed test failure for log(2+O(x))
Added basic tests for automatic series evaluation
Handle O() with multiple symbols, expand powers with deep=False
Added test: automatic series expansion should't expand anything but terms with O()
drop newline at eof
Add XFAIL test for log(x + O(x**2))