Merge branch 'doubles' into complex

Conflicts:
	symengine_version.txt

Author: rajithv

.rspec

@@ -1,2 +1,2 @@
+--require ./spec/spec_helper.rb
 --color
---require spec_helper

lib/symengine/basic.rb

@@ -2,6 +2,10 @@
 
 module SymEngine
   class Basic
+    def inspect
+      "#<#{self.class}(#{to_s})>"
+    end
+
     def free_symbols
       pr_free_symbols.to_set
     end