update SymPy

• drops support for v0.6
• edits to make v0.7 and v1.0 work: involves some removals/degradations min and max degradation; ifelse removal; base on v0.7; generic Symmetric doesn't work on matrices; sympy"" degradation

update SymPy

updates for v0.7

This has some small breaking changes for use with julia version 0.7:

• ifelse nolonger has a method
• max and min have a tighter signature with Sym objects
• boilerplate documentation is no longer present

update SymPy

• add combinatorics/permutation group module
• updates to plot recipe
• drop v0.5; using newer v0.6+ syntax for parametric function, type definitions

collected fixes

Merge pull request #192 from cdsousa/master

Fix CSE for scalar and array cases

update SymPy

Some collected fixes

update SymPy

v0.6 updates
fix round

update SymPy

flipsign, matrix improvements, free_symbols, widen type signatures for arrays, bug fixes

update SymPy

• changes to special functions
• physics package
• clean up atan2, hypot
• remove pyeval, use pycall smarter, drop SymMatrix
• bug fixes