Revert "Remove markdown from git tracking (#139)"

This reverts commit bbb6e3f309.

markdown/bitburner.hacknetserversformulas.cacheupgradecost.md

@@ -0,0 +1,27 @@
+<!-- Do not edit this file. It is automatically generated by API Documenter. -->
+
+[Home](./index.md) &gt; [bitburner](./bitburner.md) &gt; [HacknetServersFormulas](./bitburner.hacknetserversformulas.md) &gt; [cacheUpgradeCost](./bitburner.hacknetserversformulas.cacheupgradecost.md)
+
+## HacknetServersFormulas.cacheUpgradeCost() method
+
+Calculate cost of upgrading hacknet server cache.
+
+<b>Signature:</b>
+
+```typescript
+cacheUpgradeCost(startingCache: number, extraCache?: number): number;
+```
+
+## Parameters
+
+|  Parameter | Type | Description |
+|  --- | --- | --- |
+|  startingCache | number | starting cache level |
+|  extraCache | number | amount of levels of cache to purchase (defaults to 1) |
+
+<b>Returns:</b>
+
+number
+
+The calculated cost.
+