Develop sticky merge

[emolinab]

This pull request includes:
Updates about requested changes

• Added modifications to the CHANGELOG.md
• Runtimes c200 (GAMS)
  default: (00:30:07)
  Sticky: (04:08:51)
• Changes made to magpie4 to make sure costs are properly reported and that there are no conflicts with previous versions

FIRST COMMENTS

• The Sticky realization for global values of the capital and immobile capital shares.
• Two start scripts commonly used when running the Sticky realization. One for sticky default, and the other for high-resolution runs ("exo" trade realization).
• Overall costs (accumulation of previous annuities from the investment decisions) of TC, land conversion, and AEI migrated to postsolve. WARNING! The aforementioned means that the costs reported at each time step for these realizations would only include the annuity of the investment decision at the current time step from now on.