Fix __str__() to have correct alignment

Fix __str__() to have correct alignment in `DynParams` and `GeoParams`
classes.
Update corresponding __repr__() accordingly.
Add methods to update geometric and dynamic params

Add methods to update the geometric and dynamic parameters of the robot.
The method is called update_params().
Add put_val() method to communicate with the user interface. The
put_val() method updates the parameters by calling the update_params()
method.
NOTE: Currently only geometric and dynamic parameters can be updated.
Modify order of base parameters in UI
Add method to update miscellaneous parameters

Modify `update_params()` method to update some other parameter values.
Move update of geometric and dynamic parameters to separate private
method - `_update_dyns_geos()`.
Add `_update_misc()` method to do the actual update of miscellaneous
parameter values.
Add `stiffness` attribute to `FloatingRobot` class.
--All changes in `FloatingRobot` class--
Remove `pysymoro/manipulator.py`
Add UI fields for joint flexibility and stiffness
Remove dependency on `*_head` terms from `Robot` class
Add temp support for flexible joints in `Robot` class

Add temporary support for flexible joint parameters in `Robot` class.
This is mainly not to break the communication with the UI.
Merge branch 'geom_revamp' into floating
Add `get_val()` method to `FloatingRobot` class
Add floating base and WMR fields to UI
Add printing of joint params in table format

Add printing of joint params in table format in __str__() of
`FloatingRobot` class.
Fix scrollable area in Visualisation

Fix scrollable area for joint variables display in Visualisation window.
Rename `pysymoro/floatr.py` to `pysymoro/robotf.py`
Add methods to return axis values

Add method to return axis values in `GeoParams` class. The `zunit`
method returns the unit vector along z-axis and the `axisa` method
returns the joint axis in screw form.
Add `pysymoro/dynmodel.py`
Merge remote-tracking branch 'origin/floating' into geom_revamp