* wip: adds boilerplate fmi and fmu c interface

* adds working example FMU model import

* adds wrappers for doStep getReal and setReal

* fix issue with getting c++ obj pointer

* wip: debugging illegal fmu state after init

* wip: debugging illegal fmu state after init

* adds example FMU import

* adds calls to enter and exitInitilizationMode to setupExperiment and adds output to fmu step example

* adds verbosity flag for c/c++ interface fns

* remove extraneous module imports in fmu2_f_api

* example fmu step test now runs to endTime of 0.1s

* wraps clear get/setInteger and get/setBoolean

* parse the FMU XML modelDescription on init

* enables xml parser to handle FMU born XML files and adds getValueRef and getCausality methods to FMU wrapper

* wip: get and set FMU state for FMU setRestart and rewindToRestart functionality

* adds convinience method to get and set FMU variables

* wip: adds capability to setRestart and rewindToRestart and adds ex use of rewind in exampleFMU

* cleanup

* ensure GetSetFMUstate capability is enabled by checking FMU XML

* remove debug edits

* clean up unused vars

* read the FMU guid and modelIdentifier directly from the FMU XML if available

* make opaque pointer to fmu obj a property of the FMU_base abstract class

* remove unused FMUv1 specific code

* fix cmake msg status for fmu wrapper config

* adding check for duplicate variables in fmu xml

* fix issue where rewind state does not rewind model time

* retab fmu cpp files

* adding tests for fmu xml parse and fmu model load

* adds test to step fmu model forward and check against expected result

* update license and doc strings

* clean comments in fmu examples

* remove write statement from fmu unit test

* fix doc strings in FMU_Wrapper

* remove extra import c_ptr statements in FMU_f_api

* updates fmu wrapper doc strings and changes fmu interface module name

* Seperate base, Co-Sim and Model Exchange FMU types in the FMU wrapper

* wip: adds initial support for model exchange fmus in the FMU_wrapper

* deduce the number of continuous state variables from the fmu xml file for model exchange fmus

* fixes xml parse issue when a ModelStructure block is present but empty in the FMU XML

* change fmu var get and set interfaces to take character strings rather than StringType

* remove abstract interface for method that is specific to FMIv2 and v1, but not included in v3

* adds additional check to valueReference in FMU_Wrapper unit test

* make properties and methods of the abstract fmu base class private by default

* adds option to auto download the third party FMUs and gold result files in the FMU examples

* adds detailed description of each FMU Wrapper example

* adds rewind consitency check to exampleFMU2_rectifier.f90

* fix whitespace

* fix whitespace in fmu wrapper unittest