Merge pull request #188 from CEED/fort-mem-leak

Simplify accessing of inner context

Fix small mem leak in Fortran QFunctions

Add t401 to test QFunction with context

Getters updated for fCtx values

Improve QFunction ctx for Fortran interface

Make style

Vector inputs for BasisApply and QFApply; CPU backends, OCCA, and tests converted

Make style

Modify SetBackendFunction to prevent misuse

Improve operator field frees

Add global NUM_BACKEND, fix qf user pointer getter

Add setters, remove impl header from CPU, OCCA backends

Updated error message for GetArrayRead

Check for access lock on RestoreArray

Check for readers before setting array

CeedVecs - Check for read access before granting write access

lmode documentation update

Add lmode field to CeedOperatorSetField

Add Operator/QFunction field getters

Update documentation

Separate to 3 header files

First round of getters

Use Getters in ref backend

Add Getters to blocked backend

Convert OCCA backend to use Getters

Add getters for backend data

Switch held ref ceed to delegate ceed recursively checked for

Refactor to standardize backend create functions