Fix qcircuit figure and caption

See #14

Author: Ilia Lazarev

.gitignore

@@ -1,3 +1,6 @@
+.DS_Store
+.buffer
+
 ## Core latex/pdflatex auxiliary files:
 *.aux
 *.lof
@@ -19,7 +22,7 @@
 # these rules might exclude image files for figures etc.
 # *.ps
 # *.eps
-# *.pdf
+*.pdf
 
 ## Generated if empty string is given at "Please type another file name for output:"
 .pdf