Update: README.md

README.md

 
 ***Supported callers***
 
+**All callers are not activated by default**, which means the default setting is `false`. 
+You need to manually set the caller to `true` in the submitted sample.csv.
+
 **Germline**
 * Haplotyper
 
+If you only want to call germline variants, please set `germline` to true.
+
 **Somatic**
 * TNseq (TNhaplotyper2)
 * TNscope