Transitions updated to allow flush shoulders

• Modify transitions to allow shoulders that match the end diameter
• Update part database
• Update translations

Fix error reading materials

Fixes an issue reading materials that produced incorrect shear modulus
Updates to the parts database
Latest translations
New unit tests

Feature updates

This release upgrades a number of existing features:

• Add coupler option to fin cans
• Add cross and bar attachment options to transitions similar to what's available for nose cones
• Fin flutter dialog adds a chart showing flutter and divergence with altitude

Geometry bug fixes

Correct geometry issues with blunted ogive nose cones and airfoiled fins.

Also some translations added and updates to the parts database

Fin flutter analysis on non-square profiles

This release improves upon the previous release by adding support for non-square fin profiles. This includes airfoils, leading and trailing edge tapers, and many other common fin shapes.

Also included:

• Parts database updates
• Translation updates

Fin Flutter Analysis

This release allows the user to analyze a fin for fin flutter effects. The current implementation has some limitations but is useful enough that it is worth releasing as is.

Features:

• Fin flutter is calculated using the method outlined in NACA Technical Note 4197
• Atmospheric model is coesa76, an extension of the US Standard Atmospheric model that works above 84 km altitude
• Material editor allowing you to create your own material presets

Current limitations:

• Trapezoidal fins only supported at this time. Elliptical and custom fin shapes are not
• The software assumes uniform thickness. Tapers, airfoils, etc are ignored.
• Material information is not saved with the fin. It will need to be reloaded each time

Improved parts database

Replaced the stale Open Rocket parts database with the curated database from Dave Cook (https://github.com/dbcook/openrocket-database). This is the database Open Rocket will be using for all releases going forward.

Reverted issue #21 due to unacceptable performance issues.

New nose cone base styles

This release adds the option to create a bar or cross at the base of a nose cone when using the capped nose cone style

Fin cans and bug fixes

New Features:

• Fin cans
  Bug Fixes:
• #29 The width of the number input fields is too short
• #21 Correct sorting of numerical fields in component lookups

UI fixes

This release addresses the following issues:

• For secant ogive nose cones, the Ogive Radius parameter is changed to Ogive Diameter for consistency with other parameters
• Improve consistency checks for blunted cones and secant ogives to ensure parameters are in range
• Fix Issue #27 where selecting "Transform" for an object from its right click menu launched the part editor instead of activating the Transform functionality