fix naming issue
trigger_synth no longer allows varargs, merge buffer info in first
Add chord functionality:

chord(tonic, name)

Examples:

    chord(:C4, :major)
    chord(:Eb, :major7)

Caveat:

Currently not all chords are associated with valid symbols. However, they
are accessible via strings.

Valid chord names:

````
"1"          
"5"          
"+5"         
"m+5"        
"sus2"       
"sus4"       
"6"          
"m6"         
"7sus2"      
"7sus4"      
"7-5"        
"m7-5"       
"7+5"        
"m7+5"       
"9"          
"m9"         
"m7+9"       
"maj9"       
"9sus4"      
"6*9"        
"m6*9"       
"7-9"        
"m7-9"       
"7-10"       
"9+5"        
"m9+5"       
"7+5-9"      
"m7+5-9"     
"11"         
"m11"        
"maj11"      
"11+"        
"m11+"       
"13"         
"m13"        
"major"      
"M"          
"minor"      
"m"          
"major7"     
"dom7"       
"7"          
"M7"         
"minor7"     
"m7"         
"augmented"  
"a"          
"diminished" 
"dim"        
"i"          
"diminished7"
"dim7"       
"i7"  
````
Allow scales to be addressed via strings
Improve printing to end user