Line3D class
Added new methods along the Ray class
Added the remaining methods
Added tests
Changed the __eq__ method and added the equal method
Small change
Code cleanup
Removed hash and __eq__ methods
Rewrite lambda as a function.  This avoids a runtime error (i.e. return
value of cached and not cached function differ)  with

SYMPY_USE_CACHE=debug py.test -x sympy/integrals/tests/test_trigonometry.py
Make sympy_parser work with evaluate=0. Fixes #7663
Test with Mul's instance instead of expr
6939: watch for exact values in calc_part

If an mpf tuple (n, c, p, b) if c==1 or p==0 then this
represents an integer so no special processing is needed
in calc_part.
Corrections to core.symbol.symbols docstring

Made clarifications to paragraph describing range syntax.
Add command to exit on error(build_doc.sh)
It is important to exit on error and not delete all the doc files and push an empty dev folder
Merge pull request #7668 from debugger22/auto-deploy-dev-doc

Add command to exit on error(build_doc.sh)
Merge pull request #7665 from smichr/6939

ceiling(x).n(subs={x:3}) now works; fixes #6939
Merge pull request #7664 from debugger22/parse_expr_evaluate_int

Make sympy_parser work with evaluate=0. Fixes #7663
Merge pull request #7658 from pbrady/cache_debug_fix

SYMPY_USE_CACHE=debug results in errors
Merge pull request #7666 from jvsiratt/correction_symbols_doc

Corrections to core.symbol.symbols docstring
Add John V. Siratt to AUTHORS/aboutus. Welcome to SymPy