Fixed bugs in docs/install.md

Makefile

@@ -229,7 +229,7 @@ help_client:
 	@echo "  build_nexush        Build nexush; require the SERVER variable and optionally"
 	@echo "                      CERT (see below)"
 	@echo "  build_nexus-cli     Build nexus-cli; same as above"
-	@echo "  build_nexus-exam    Build nexus-exam; require the SERVER_IP variable"
+	@echo "  build_nexus-exam    Build nexus-exam"
 	@echo "  xbuild_client       Cross-build $(BIN) for Linux, Windows, Darwin (OSX)"
 	@echo "                      Require the BIN variable which specifies which binary to"
 	@echo "                      cross-build: nexush or nexus-cli"
@@ -295,7 +295,7 @@ build_nexus-cli: check_server_var copy_resources_client $(BUILD_DIR_CLIENT) $(SR
 	@echo "[Building nexus-cli into $(BUILD_DIR_CLIENT) directory]" 
 	@cd $(SRC_CLIENT)/nexus-cli && go $(BUILD_CLIENT_FLAGS) && mv nexus-cli $(BUILD_ABS_CLIENT)
 
-build_nexus-exam: check_serverip_var copy_resources_client $(BUILD_DIR_CLIENT) $(SRC_CLIENT)/nexus-exam
+build_nexus-exam: $(BUILD_DIR_CLIENT) $(SRC_CLIENT)/nexus-exam
 	@echo "[Building nexus-exam into $(BUILD_DIR_CLIENT) directory]"
 	@cd $(SRC_CLIENT)/nexus-exam && go $(BUILD_CLIENT_FLAGS) && mv nexus-exam $(BUILD_ABS_CLIENT)
 	@strip -s $(BUILD_DIR_CLIENT)/nexus-exam

docs/install.md

@@ -260,14 +260,14 @@ The `SERVER_IP` environment variable is required. It defines the nexus-server ip
 For now, the only supported combination of OS and architecture for nexus-exam is Linux/amd64. Furthermore, it cannot be built statically as some static libraries are missing.
 
 ```sh
-make build_nexus-exam SERVER_IP=10.0.2.15
+make build_nexus-exam
 ```
 
 Running nexus-exam requires the `CERT` environment variable. It specifies the directory where the public certificate `ca-cert.pem` resides (typically in `nexus-server/certs/`).
 
 To run it:
 ```sh
-make run_nexus-exam CERT=$HOME SERVER_IP=10.0.2.15
+CERT=$HOME SERVER_IP=10.0.2.15 make run_nexus-exam
 ```
 
 ## Deleting all nexus clients