Release 0.9.11 "Prayer" - Uncertain numbers

This release implements arithmetic and basic functions on uncertain numbers.
This propagates uncertainty using quadradic superposition, in a way similar to OpenRPNCalc, with a generalization for correlated variables.

New features

• Arithmetic and basic functions on uncertain numbers
• Add support for complex-valued unit objects, e.g. 5+3ⅈ Ω
• Add support for range-valued unit objects, e.g. 1…3 Ω
• Support arithmetic operation on infinities, e.g. ∞ 42 +
• Add commands to generate mathematical constants (π, ℮, ∞ and −∞)
• Parsing and editing of ranges containing infinities
• Accept infinities in →Range and variants
• Comparison of infinite values and finite values
• Add union and intersection commands for ranges
• Add operations to build ranges and uncertain numbers from components
• Add derivative for erf and erfc

Bug fixes

• Do not leave bad expressions behind after errors on ranges
• Obey the InfinityError flag when detecting divide-by-zero in ranges
• Avoid crash pushing null pointer after unit evaluation error
• Avoid spurious inconsistent units error due to date computations
• Null-protection in variadic list::make, fixes null-deref crash

Improvements

• Accelerate error exit from arithmetic operations
• Render uncertain numbers as 110±σ15 instead of 110±15σ
• Accept − as valid input in constants (for −∞)
• Record performance data for iPhone 16
• Change spelling to →σRange in RangeMenu
• Use ASSERT for divide by zero inner checks (remove dead code)