set isDev as default if there is no blockchain file

lib/cmd.js

@@ -105,6 +105,10 @@ class Cmd {
         _options.logLevel = _options.loglevel; // fix casing
         _options.onlyCompile = _options.contracts;
         _options.client = _options.client || 'geth';
+        embark.initConfig(env || 'development', {
+          embarkConfig: 'embark.json',
+          interceptLogs: false
+        });
         embark.build(_options);
       });
   }
@@ -217,6 +221,10 @@ class Cmd {
         _options.logFile = _options.logfile; // fix casing
         _options.logLevel = _options.loglevel; // fix casing
         _options.client = _options.client || 'geth';
+        embark.initConfig(env || 'development', {
+          embarkConfig: 'embark.json',
+          interceptLogs: false
+        });
         embark.upload(_options);
       });
   }
@@ -231,6 +239,10 @@ class Cmd {
       .description(__('generates documentation based on the smart contracts configured'))
       .action(function (env, options) {
         i18n.setOrDetectLocale(options.locale);
+        embark.initConfig(env || 'development', {
+          embarkConfig: 'embark.json',
+          interceptLogs: false
+        });
         embark.graph({
           env: env || 'development',
           logFile: options.logfile,

lib/core/config.js

@@ -180,6 +180,9 @@ Config.prototype.loadBlockchainConfigFile = function() {
   let configFilePath = this._getFileOrOject(this.configDir, 'blockchain', 'blockchain');
 
   this.blockchainConfig = this._mergeConfig(configFilePath, configObject, this.env, true);
+  if (!configFilePath) {
+    this.blockchainConfig.default = true;
+  }
 };
 
 Config.prototype.loadContractsConfigFile = function() {

lib/index.js

@@ -35,7 +35,7 @@ class Embark {
   }
 
   isDev() {
-    return this.config && this.config.blockchainConfig && this.config.blockchainConfig.isDev;
+    return this.config && this.config.blockchainConfig && (this.config.blockchainConfig.isDev || this.config.blockchainConfig.default);
   }
 
   blockchain(env, client) {