feat!: restructure erstie guide, expand

Expanded the erstie guide massively (added guide for each semester),
restructured to new URLs, added summaries details

summaries/semester2.md

@@ -1 +1,21 @@
 # Semester 2
+## Analysis I
+My own cheat sheet is not all that great in terms of layout, as it was still written with my (woefully inept for compact Cheat Sheets) old helper files.
+It however has both a German and English version.
+<small>*(It happened to be in both language because I did not realize that the exam would be in German and it would probably be smart to have it in German, too)*</small>
+- [Cheat-Sheet (EN & DE)](https://github.com/janishutz/eth-summaries/blob/main/semester2/analysis-i/cheat-sheet-jh/README.md) Author: Janis Hutz
+- [Cheat-Sheet (DE)](https://github.com/janishutz/eth-summaries/blob/main/semester2/analysis-i/cheat-sheet-rb/main.pdf) Author: Robin Bacher
+
+
+## Algorithms and Probability
+A summary of the complete course, mostly suitable as a script replacement, albeit the script is quite good
+- [Summary (EN)](https://github.com/janishutz/eth-summaries/blob/main/semester2/algorithms-and-probability/aw-summary.pdf) Author: Janis Hutz
+
+## Parallel Programming
+Similar in concept to the EProg compact summary, giving you a *very* brief overview of the central concepts
+- [Compact Summary (EN)](https://github.com/janishutz/eth-summaries/blob/main/semester2/parallel-programming-compact/pprog-compact-summary.pdf) Author: Janis Hutz
+
+## DDCA
+Since for DDCA, the Cheat-Sheet needs to be handwritten, it is not in the git repo, as my other Cheat-Sheets are
+- [Cheat-Sheet PDF](https://exams.vis.ethz.ch/user/jahutz/document/ddca-cheat-sheet-fs25_0) Author: Janis Hutz
+- [Cheat-Sheet Goodnotes file](https://static.janishutz.com/ETH/DDCA-CheatSheet-janishutz.goodnotes) Author: Janis Hutz