Parameterized LLD macro name.

Prior to this commit, macro name used in prototyped item key was '{#MBEAN}'
for all discovered items.  This was causing conflicts when non-LLD-portion
of prototyped item key was same between discovery rules.

Additional positional argument was introduced to address this problem by
changing macro name for each discovery rule.
Merge pull request #2 from daniel-star/parameterized-lld-macro-name

Parameterized LLD macro name.