Sympad

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* Finally put sympad on PyPI.
* Major grammar rework to remove redundant conflicts for speedup and to better handle tail elements (!, ', **, .attr, [idx], (x, y, ...)), \int, \sum and \lim among other things.
* Added symbols with assumptions.
* Added ability to 'call' derivatives of lambda functions.
* Added parsing of 'not' as possible unary prefix to unparenthesized function arguments.
* Added differentiation of parentheses grouping vs. call via curly enclosed parentheses.
* Added mapping of undefined functions back to the variables they are assigned to.
* Added partial differential equation support.
* Added ability to select display of leading rational of products.
* Added parsing of LaTeX subscripts in \operatorname.
* Added ability to select strict or loose LaTeX formatting.
* Made supported builtin functions accessible directly by name without need of escape character.
* Made Eq returned from SymPy display as = when unambiguous in grammar.
* Brought quick mode up to date with many recent changes.
* Re-enabled unspaced quick mode function arguments.
* Lots of tweaks to undefined functions for display and use in assignment to lambdas.
* Removed recursive execution of script and relegated it to a command line switch for development.
* Finally documented lots of changes.

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* Added parsing and writing of initial conditions of derivatives of undefined functions in function format (complicated).
* Added proper formatting of exceptions which contain newlines in the exception text.
* Added error hint text to web client.
* Improved unparenthesized argument parsing for functions.
* Improved error reporting from the parser.
* Fixed "d / dx (a) b" and "\frac{d}{dx} (a) b" to work properly.

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* Added variable stack frames to variable mapping.
* Added remapping of differentials in derivatives and integrals.
* Changed lambdas to not automatically bind global variables if they have the same names as parameters, instead they can be accessed with ().
* Changed lambdas to not automatically doit() their body upon definition by default instead of needing the no-eval pseudo-function.
* Improved assignment parsing to handle assignment to undefined functions better (creation of lambdas).
* Moved SymPy .doit() from per-object level to end of whole evaluation since it can interfere with certain calculations.

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* Added explicit substitution shorthand and AST.
* Added undefined function parsing and writing of immediate value arguments for initial conditions.
* Changed to allow implicit undefined functions as exponents for grammatical consistency.
* Changed some ordering for negatives to display simpler additive terms.
* Fixed some annoying cases where fractions were displayed in the numerator of another fraction instead of being absorbed into it.
* Fixed certain tokens which were not being gramatically rejected as they should have been with a trailing \w.

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* Added early out for successful parse if all remaining conflicts are trivial reductions.
* Fixes, randomized testing no longer returning any errors.

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* Extended recognition of single unparenthesized arguments to functions - "N ln sin**2 3" is valid now.
* Added union, intersection and symmetric difference unicode characters.
* Added more thorough test cases to test_sym.
* Changed And() parsing to more reliably recover original extended comparisons from mangled SymPy representation.
* Tweaked lambda / slice / dict parsing and writing to be more comprehensive.
* Fixed even more esoteric grammar inconsistencies.