Added first proposition

- Added first proposition and some basic definitions used
Added second proposition
Added New Problems

- Stuck on Example 5.57 (iv), p 274, Rotman
Rewrote some proofs
Base Commit
Added some theorems about protosheafs
Up to subetale-sheaves
Added nice example
Added proof of exact sequence
Added Equalizer Theorem
Finally defined what a real sheaf is
Added interesting result
Update Alternate Defn. of Stalk
Added Stalk Proof
Finished
Changed font size
Create mk_derived_functors
Delete mk_derived_functors
Added some reasoning behind Skyscraper Sheaf
Finished Skyscraper Sheaf example